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I Know What You Did Last Summer

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Four teens fight to outsmart a killer who intends to avenge a young boy's death in this suspenseful thriller that inspired the classic horror film.
After a party, four teens are in a hit-and-run accident that results in a young boy's death. Unable to deal with the consequences, they leave the body behind and make an anonymous phone call to the police, tipping them off.
The group makes a secret pact to bury the memory of that night and never speak of it again, but when one of the girls receives a note that reads "I know what you did last summer," their dark lie is unearthed. With twists and turns at every corner, they'll have to fight to stay steps ahead of a killer determined to make them pay.

240 pages, Paperback

First published October 1, 1973

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15.1k people want to read

About the author

Lois Duncan

61 books1,948 followers
Lois Duncan (born Lois Duncan Steinmetz) was an American writer and novelist, known primarily for her books for children and young adults, in particular (and some times controversially considering her young readership) crime thrillers. Duncan's parents were the noted magazine photographers Lois Steinmetz and Joseph Janney Steinmetz. She was born in Philadelphia, Pennsylvania, but grew up in Sarasota, Florida. Duncan started writing and submitting manuscripts to magazines at the age of ten, and when she was thirteen succeeded in selling her first story.

Duncan attended Duke University from 1952 to 1953 but dropped out, married, and started a family. During this time, she continued to write and publish magazine articles; over the course of her career, she has published more than 300 articles, in magazines such as Ladies' Home Journal, Redbook, McCall's, Good Housekeeping, and Reader's Digest. After her first marriage, which produced three children, ended in divorce, Duncan moved to Albuquerque, New Mexico, to teach journalism at the University of New Mexico, where she also earned a BA in English in 1977. In 1965 she married Don Arquette, and had two more children with him.

Duncan was best known for her novels of suspense for teenagers. Some of her works have been adapted for the screen, the most famous example being the 1997 film I Know What You Did Last Summer, adapted from her novel of the same title. Other made-for-TV movies include Stranger with My Face, Killing Mr. Griffin, Don't Look Behind You, Summer of Fear and Gallows Hill.

In 1989 the youngest of Duncan's children, Kaitlyn Arquette, was murdered in Albuquerque, New Mexico, under suspicious circumstances. Who Killed My Daughter? relates the facts and conjecture about the still unsolved case.

Duncan's second book about her daughter's murder, ONE TO THE WOLVES: ON THE TRAIL OF A KILLER, picks up where the first book leaves off and contains all the new information Kait's family has uncovered from private investigation.

The 1971 children's book Hotel for Dogs was released as a theatrical movie in 2009, starring Emma Roberts. That book has now been republished by Scholastic along with two sequels, News for Dogs (2009) and Movie for Dogs (2010).

Duncan's Gothic suspense novel, DOWN A DARK HALL, is being filmed for the Big Screen and will probably be released in 2016.


Follow Lois on Twitter: http://twitter.com/duncanauthor
http://www.facebook.com/profile.php?i...
http://www.kaitarquette.arquettes.com

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Displaying 1 - 30 of 1,994 reviews
Profile Image for Joe.
520 reviews1,077 followers
September 5, 2016
Before it was a '90s slasher movie, I Know What You Did Last Summer was actually a novel by Lois Duncan and believe it or not, a very good one. Published in 1973 and revised by the author in 2010, I had superficial issues with her decision to rebrand everything from fashion to geopolitics to telephones for the Young Adult reader of today--a decision that felt financial as opposed to creative--but where it matters, the book generates a terrific amount of suspense and delivers a satisfying payoff without throwing graphic violence, sex or much foul language at the reader. In this sense, it's more like an Alfred Hitchcock thriller with teens than slasher fare.

Set in the vicinity of Silver Spring, Maryland with its mountain roads, the story begins with high school graduate Julie James getting summer off to a promising start when an acceptance letter to Smith College, the alma mater of her widowed mother, arrives in the mail. Mrs. James has sensed a change in her redheaded cheerleader daughter over the last year, studying harder but having less fun, breaking up with a boy named Ray Bronson, who left town about a year ago and headed to California. Julie almost ignores a second letter she's received, one with no return address on the envelope. The message in big block printing ominously reads I KNOW WHAT YOU DID LAST SUMMER.

We next meet Barry Cox, freshman at the local college and a football hero in his high school days whose winning ways still get the attention of the girls. For this reason and others, Barry has cooled to his girlfriend of the past year, Helen Rivers, a high school dropout whose ambition and golden looks have secured her a lucrative job with Channel Five as a station rep and on-air personality. Helen's success seems to be the only reason Barry hasn't broken up with her and when she telephones with something important to talk with him about, he has no choice but go to her apartment complex. Barry finds Julie there as well, who shares the threatening letter with the couple.

Making reference to a "pact" they made last summer, Barry blames the letter on Ray, who Helen reveals is back in town. Neither of the women believe Julie's ex would do something like this. The football hero offers that Julie might be getting teased about something else she did last summer. Helen is not comforted by this. Julie returns home to prepare for a date when she encounters Ray waiting for her. While he's missed Julie, she explains that she needs to move on, haunted by a tragic accident in which the car that Barry was driving with Helen in the front passenger seat and Julie & Ray in back struck a twelve-year old boy on a bicycle named Daniel Gregg.

Driving too fast while under the influence of a few beers and a little pot, Barry feared prosecution and fled the accident scene that night. Julie's vocal plea that they go back to help the boy was opposed by Helen, who then as well as now is in love with Barry and wants to protect him. Casting the deciding vote to stay silent was Ray, who at that time lacked the nerve to stand up to Barry and instead made an anonymous call to 911. Their victim died on the way to the hospital. Julie shares her letter with her ex, dreading that someone else knows their secret. Ray believes they should confess to the police, not breaking the pact, but dissolving it by convincing Barry and Helen to agree with them.

While Julie makes a fresh start with an Iraq war veteran she's dating named Bud, Helen continues to feel distance from Barry. Growing up in a low income household and sharing a bedroom with her dumpy and vindictive older sister Elsa, Helen's self-made success and minor celebrity has only made her feel more ostracized by her family and peers. She makes a friend with a handsome new neighbor named Collie but comes close to falling apart when Barry is lured away from his frat house by a telephone call and shot. His ability to walk again in doubt, Barry claims that the phone call came from Helen, who denies this. By now, both Helen and Ray have received ominous messages as well.

Taking the initiative, Julie and Ray go up up to Mountain Highway to visit the Greggs. They meet Daniel Gregg's sister Megan, who reveals that her mother blamed herself for Daniel's death and fell ill. She's convalescing in Las Lunas with her father. Julie is certain that none of the Greggs could be responsible for the threats, while Ray notices a fresh coat of paint on the house and men's shirts drying on the clothesline. The mystery thickens when Ray sneaks into the hospital to confront Barry about his fatal phone call. He conceals the truth, which is that a caller threatened to blackmail him with photos of the accident and lured Barry into a meeting, where he was shot.

Meanwhile, Mrs. James has a very bad feeling about all of this.

Not that the feelings were foolproof and could be taken as gospel. Last summer, for instance, there had been a time when she could have sworn that she felt something terrible approaching. It was during a period in which Julie was seeing a great deal of Ray, and for a while Mrs. James had wondered if that was it, if the young people's feelings for each other were growing too strong and would create a problem. Fond as she was of Ray, she was aware of his immaturity, and she wanted another year of high school for Julie and then hopefully college. The idea of an unwed pregnancy or a very young marriage was not easy for her to accept.

In the 2010 revision of I Know What You Did Last Summer, Lois Duncan made a number of superficial changes to her 1973 text. A few are hard to spot, like a blue pantsuit changing to blue pants and a blouse. Vietnam and an antiwar demonstration are changed to Iraq and an indiscriminate campus demonstration. A noticeable change is the juggling act Duncan has to do with mobile phones, which could have solved her mystery in half an hour if characters were easily able to contact each other or authorities in an emergency. In the inferior revised edition, all manner of dead batteries, dropped signals or landlines still strangely in use are offered to keep the plot going.

There are reasons why a novel written in the 1970s or '80s should not be revised for the Information Age, even a novel that on the surface seems to be little more than a Young Adult thriller. The world has changed so much in forty years that relabeling is not sufficient to pass Duncan's story off as one that could take place today. The catalyst of I Know What You Did Last Summer is a boy on a bicycle being struck by a hit and run driver at ten o'clock at night, plausible and effective in 1973, but today, when all bicycles have reflectors and all children are cocooned in safety gear, not to mention guarded by anxious parents who rarely let their children out of sight, this scenario feels like a stretch.

This sort of reboot feels more like a financial gambit than one made to improve quality of the book and I Know What You Did Last Summer is compelling enough not to need it. Duncan does a wonderfully subtle job of generating tension with characters who've committed an irrevocable crime and are wrapped so tight with guilt that the slightest tug might force them to snap. This is a thriller where I was able to feel empathy not only with the protagonists, but their tormentor, who unlike the boogeyman in the derivative 1997 slasher film and its sequels, inflicts psychic violence as opposed to mostly physical. The reveal in his identity, also altered for the movies, is novel as well.

Duncan, who allows her teenagers some illegal substances but lets the reader imagine how much sex they've experimented with, should be respected for writing a terrifying book without racking up dead bodies. More sinister and imaginative is how Duncan keeps the teenagers alive. In addition to the guilt that's been building over a year, each character is dragged into their own level of hell. A sports hero , a beauty queen has to , a college student and the boy who loves has to watch. It's a restrained, evocative thriller and one I more often that not found myself able to relate to.
Profile Image for Bren fall in love with the sea..
1,842 reviews406 followers
November 12, 2024
“Girls like her are a dime a dozen, and I happen to have a pocket full of dimes.”
― Lois Duncan, I Know What You Did Last Summer




One is never to old to read the classic mystery "I know what you did last summer" which was also a movie (not a very good one) and spawned many a copy c at book with a similiar premise.

I first read this as a kid. I am a huge fan of Louis Duncan's work and this was one of her best novels. The premise is simple. A group of 4 teenagers, out late one night, partying it up, hit a boy on a bike and do not stop. They make a pact to keep what happened a secret.

One year later, Julie James one of the members of said pact, receives a letter in the mail. All it says is:

I KNOW WHAT YOU DID LAST SUMMER.

This book was so damn good. And I sort of wish the movie spin off had not happened as they took the original premise..and it WAS original back then..and turned it into a horror/slasher movie which in my opinion is unforgivable given that the original book was so readable. I would have liked to see the film follow the book.

What is also great are the characterizations. Duncan was always so good at that. You feel you know everyone from Julie to her sweet mom to Ray to Helen and her sullen sister to Barry the ultimate jock and frat boy. It is short book but it demands attention and honestly if you are in your adult years and have not read it, you would most likely like it.

SPOILERS!

Back then, twists were not an every day thing as they are now so when Duncan did a stunner of one in this book, it was actually a surprise.

I have reread this a few times and I always love it. Nostalgia is no doubt one reason but there is also no getting around the fact that it's a mighty fine book. Read the book, skip the movie.
Profile Image for megs_bookrack.
2,037 reviews13.2k followers
July 5, 2024
Another nostalgic read from one of the pioneers in YA Thrillers, Lois Duncan!!



Originally published in 1973, Lois Duncan's I Know What You Did Last Summer paved the way for all the YA Thrillers that have come after.

Most of us are familiar with the 1997-film adaptation starring Jennifer Love Hewitt and Sarah Michelle Gellar. Honestly, that was one of my go-to movies in the 90s and 2000s, yet I didn't even know it was adapted from a book until a few years ago.

I bought a copy and have been meaning to read it forever...



Recently, I listened to the audiobook for another of Duncan's novels, Killing Mr. Griffin, and I had so much fun with it. It was quick, nostalgic and drama-filled. I knew when I was done with that, it was finally time for me to read this one.

I decided to listen to the audiobook in this case as well. It was read by the same narrator and I liked his style.



After reading this, I gotta say, they did a great job with the adaptation. It closely followed the source material, yet with the right amount of modern twists, to make it believable and fun. I'm in love with the casting, perfection.

I am so happy that I finally took the time to read this one. I'm super into nostalgic reads right now, particularly those of the Horror and Thriller variety, so this was exactly what I was looking for.

If you are a fan of the movie, I definitely recommend you check this one out!!

Profile Image for Kelly (and the Book Boar).
2,756 reviews9,294 followers
December 22, 2017
Find all of my reviews at: http://52bookminimum.blogspot.com/

3.5 Stars

Welcome to . . . .



I decided to take a break from my usual selections . . . .



And read listen to this oldie-but-goodie to celebrate my favorite time of year . . .


(Spoiler Alert: He’s really going to murder her for being a basic white bitch.)

After having a pretty meh time with Killing Mr. Griffin during Banned Book Week, I set my expectations super low before starting this one. Imagine my delight when I ended up really enjoying it. The basic premise was the same – group of drunken stumbly teenie-boppers kill someone in a hit and run and then decide . . . .



Little plot twist: in the book version they didn’t run over an adult – instead it was a kid . . . .



A year goes by when suddenly the teens start receiving notes . . . .



That have them concerned their secret might get out. Or worse . . . . .



I Know What You Did Last Summer stood the test of time surprisingly well. While it has obviously been updated since its original release back in the ‘70s, a more thorough job was done here making the modern-day references more effortless instead of standing out like a sore thumb. It does date itself with antiquated remarks regarding things of a “girly” nature, but if you aren’t of the easily offended variety, you can simply laugh it off as talk of the olde days of yore. Although I did see the whodunit from about a football field away, there was a little something extra that I wasn’t really looking for that ended up being a pretty decent bonus. Fairly PG (references to underage drinking and smoking pot that wouldn’t pass the test with some parents) for youngsters to read this Halloween season.
Profile Image for saisha⊹(catching up!).
58 reviews160 followers
Read
March 15, 2025
𓆩♡𓆪𓍢ִ໋🏹࿔ post-read 3/14/25!

this my sign to read more thrillers now?? literallt SO GOOD OMG!! that plot twist at the end...😭🤭 xx rtc maybe!!<3


𓆩♡𓆪𓍢ִ໋🏹࿔ pre-read 3/10/25!

so excited to read this - i haven't read a good thriller in a while! also my writing+literacy teacher gave this to me and told me that i'd like it, i hope she's right!!🤭🙌🏻💌
Profile Image for Ken.
2,449 reviews1,361 followers
October 11, 2019
It wasn’t until recently that I found out that one of my favourite movies of the late 90’s was actually based on a book, but what is more surprising is how different they both feel.

I’d not realised that I was in fact reading an updated version of the story, with talk of cell phones and CDs it felt very much of that time period. It wasn’t until mentions of the Iraq war that I’d finally realised that changes had been made! Oops...

This book is clearly being aimed at people like me who have come to it because of the film, it was more suspenseful that the slasher flick and I quite enjoyed it for that.
The main plot of teens covering up a hit and run indecent is still the main part of the story.

Nostalgically I think I would have liked to have read the original version (maybe an authors note at the beginning might have helped), but I really want to give the movie a rewatch this October!
Profile Image for Steph.
757 reviews440 followers
July 7, 2024
i was pumped to read this 1970s YA suspense classic, but oh my goodness, whose idea was it to create an updated edition for the new millennium? they modernized the teen slang and added cell phones, but left the old school misogyny and fatphobia untouched. what a cringingly anachronistic read!!

the modernization is so clumsy that i was sure it was done by a miscellaneous staff member at the publishing house. i felt awful when i got to the author Q&A at the end of the book and found that duncan herself updated all of her books that were rereleased this century.

and it's quite insulting for authors or publishers to believe that modern teens are incapable of enjoying lit that was published before they were born. i mean... kids today are aware that there was a world before cell phones. and especially in a thriller like this one, where the ability to call 911 can completely alter the trajectory of the story, it just doesn't make sense. this book is filled with tacked on lines about why a given character doesn't have their cell phone at any given moment. oh my god, why did they bother?

(just kidding, i know why: they thought they could make a larger profit on the rerelease if the book was ~new and improved~ and ~relatable for younger generations~)

but the worst part is that all of the updates are superficial, and the book is dated on a much deeper level: it is steeped in misogyny. we have frat boy player barry, whose sexism repeatedly goes unchallenged. we have independent helen, who we are repeatedly told is lucky to be so beautiful, because it's all she has going for her. and there's helen's sister, elsa, who is described as fat and ugly, bitterly jealous of helen, and an overall unpleasant person. it was the 1970s, and none of this is surprising to look back on... but it is so much more disturbing when we're made to believe these outdated characters are 21st century teens.

okay, end rant.

overall, this is a well-paced suspense novel with an interesting twist. duncan's Q&A mentions that she hated that the twist was omitted from the movie version, but it would have been literally impossible to manage on screen.

apparently duncan disliked the film because of the changes to plot, and also because she had a strong aversion to violence. it's true that the book is a mysterious thriller, rather than a horror novel, so it's understandable.

one of my favorite things about reading classic YA is soaking up the vibes from another decade. and in i know what you did last summer, the 70s vibes are particularly noticeable in helen's apartment complex, a balconied building alongside an outdoor pool. all of the tenants are young singles who spend much of their time socializing poolside. we only have a few scenes in this setting, but i adored them because they feel so far from our time.

anyway. it's an entertaining read, but if you're going to pick this one up, please try to find the original version 😩
Profile Image for Darth J .
417 reviews1,295 followers
July 29, 2016
Okay guys, I read this book when I was in fourth grade (when the movie came out) so my recollection will be a little bit foggy. Just go with me on this, okay?

So the plot of this story centers on Julie James , who receives a mysterious note:


Her mind jumps to the conclusion that someone witnessed her and her three friends accidentally hitting a pedestrian last year and that this note is some sort of prank/blackmail about it. It isn't until the end that she realizes that, unlike the movie where the killer is a weird fisherman, the stalker is . Also, the Sarah Michelle Gellar character lives in the book.


If you've seen the movie and want the less slasher version of the story, pick up this book.
Profile Image for Evoli.
304 reviews106 followers
March 29, 2024
Finally came around to read this classic!
To be fair, I predicted pretty much the entire plot, which was a bit of a letdown (and no, I have not watched the movie).

Nevertheless, some psychological aspects that were there as "subplots" were really interesting to read about and I enjoyed the different perspectives that we were given from all the protagonists.
I can't really say that I sympathise with any of the protagonists in here, except for maybe slightly Julie because she was the one who was the most adamant about going back and telling everyone. I feel like she was the one who experienced guilt the most, I mean... she even sent flowers. Frankly speaking, it's hard to even sympathise with her because of the fact that she still didn't manage to convince them or just report it with breaking the pact because honestly, who cares about a silly pact when a person is dead? Exactly.

Oh, although... Looking back at it now, there is 1 person that I feel sorry for. That person is Julie's mom, Mrs. Smith. She definitely did not deserve any of that and her premonitions of something bad happening to Julie made me slightly emotional.

I'm really not sure what I think about the writing style, to be honest, so I guess I'll just reward this book with a middle-ground 3 star!
Definitely worth a read just to know what the fuss and popularity is all about.
Will it stick to me though? Hm, probably not.
Profile Image for STEPH.
478 reviews59 followers
August 23, 2024
Wow, I didn’t know that the movie was based on this book. Wasn’t it published in 1973? Pretty cool.

I read the interview log at the end of the book and discovered that a lot of changes were made for the movie. The names are the same, but the studio totally strayed from the original material—like with the killer and the attacks, for instance. The movie was a bit more violent and brutal. It’s kind of sad because even the author thought it was a different movie when she saw it in the cinema.

That said, if anyone asked which I liked better, I’d be torn. The book has an aura of mystery, dual identities, and high tension between the characters. I found myself resenting the kids in the book just as much as I resented the ones in the movie. However, the clincher for me is the amount of scares. Being a fan of serial killer movies and the like, I prefer the kills in the movie.

But, I liked this book. Considering that it’s decades older than me, I feel like I’m part of something significant.
Profile Image for Christian Guzman.
22 reviews48 followers
March 23, 2016
I read this novel in one sitting. It wasn’t the most enjoyable book I have read, but it wasn’t unexciting either. I would have probably enjoyed this novel way more if I had read it when I was about 13 years old. The concept and plot of the book grabbed my attention which is why I decided to read it. Also, the length of the book was ideal, just in case if I didn’t enjoy it I wouldn’t have wasted too much time on it. It was quite entertaining, but it lacked suspense for me. At first I found it to be captivating, but during some chapters I felt like it was predictable. I did however enjoy the main characters, I felt like they were well written and weren’t confusing to keep up with. The author didn’t flood you with an excessive amount of characters in the novel so you could easily distinguish them from one another. I felt like I was watching a horror movie as opposed to feeling as if I was in the characters' shoes. I also expected a more intense ending. Nonetheless, if you are looking for a quick read that is also entertaining, this is an adequate book!
Profile Image for PinkAmy loves books, cats and naps .
2,582 reviews250 followers
June 10, 2019
Holy dated book, Batman.

I grew up on Lois Duncan, the go to YA thriller writer in the 1970s. I might have even given I KNOW WHAT YOU DID LAST SUMMER five stars back then. Technology makes many books of my generation either period pieces or irrelevant. Teens today have never had to search for a dime for a payphone, what having an unlisted phone number means or not knowing who’s calling when you answer the phone.

Some editor had a not-so-brilliant idea to update I KNOW WHAT YOU DID LAST SUMMER by throwing in a few computers and cell phones without addressing the rampant sexism that existed when I was young. I’m paraphrasing—good thing Helen was pretty, it was all she had going for her. I could site dozens of examples of similar phrases that were awful messages for girls when I was growing up but happened all the time. Had editors left the book as was, good discussions about the differences in feminism and equality between then and now. Updated, the phrases seem Neanderthal.

Skip this, or look for the original.
Profile Image for Carla Remy.
981 reviews107 followers
August 16, 2023
Aug 2022:

I purchased a copy of this on Etsy. Probably the same printing I read in 1989 when I was 12.
Again, the changes, adding the Internet... a horrific travesty pointlessly destroying this and her other books. In 2010. Lois Duncan lived until 2016. So...
I Know What You Did Last Summer is a very good novel. Short and tight with a satisfying conclusion.

Oct 2021:
This book is from 1973. I read it in the late 1980s, when I was in junior high. So I'm happily reading it again, just now, and I come to a mention of texting. I'm still in shock, but I looked it up. The publisher updated it in 2010. I mean, what is this, George Lucas retroactive changes? Sure, the changes are probably slight but still.
Do they think kids today (or like eleven years ago) will think the book is more real feeling because it mention texting? Probably not.
Profile Image for Heathers_readss.
641 reviews93 followers
October 4, 2024
Honestly it wasn’t a bad book , the rating I gave was because all the aspects of the plot where predictable as the book went along, there was no shock factor and the characters just seemed to be lacking depth.

However for a quick read, maybe more geared towards YA age group it could be an enjoyable read
Profile Image for Vanessa.
715 reviews106 followers
September 14, 2019
I remember when this movie came out and I was like, “I swear I read a book with this title years ago.” And I had, as it turns out. By the late, great spooky mystery lite YA author, Lois Duncan. But this wasn’t just a book I had read this one time; we read excerpts from many of Duncan’s books to each other at slumber parties (with lights out and flashlights under our chins, you know, that whole deal.)

Flash forward to now: and no one has told me a ghost story involving a Lover’s Lane hook hand killer in decades I was in Half Price Books a few weeks ago buying a stack of light reading for my surgery leave when I saw a Lois Duncan novel and, although I hadn’t thought of her in years, I suddenly became convinced I absolutely needed to pick up some Lois Duncan classiques. This one was naturally a must have.

If you’ve seen the teen slasher flick from the 90’s, the body count and gore are dialed down significantly (there is an interview in the back of this edition with Duncan, who was so surprised when she saw the movie, she thought she was in the wrong theatre.) The framework of the plot is, however, the same:

Ray, Julie, Helen, and Barry are young, in love, and blessed with the bone structure of CW stars. Then they hit a child on a bicycle late one night on a dark road. In a panic and with alcohol on their breath, they agree to do a hit and run. A year later, their lives have continued more or less successfully but their friendship is mostly over. Then Julie receives an anonymous note from someone who claims to know what she did last summer. More notes follow. Are they being blackmailed, is it a harmless prank, or are they in real danger?

Does the Gorton’s fisherman wear a yellow slicker?


This was entertaining, but it’s written for a younger crowd, so as I said the violence is toned down and there’s no way you won’t identify the killer. Like, immediately. But Lois Duncan was an ace at cranking out these efficient tales and, well, I’ve got a short stack of her books in my spare bedroom now.

One of my GR friends reviewed this and mentioned she was put off by the updating of the book. Duncan herself did this for a new edition in 2010, and once you realize it’s there, it IS kind of obvious (“Oh, Helen has been calling for me? My cell phone died.” “Let’s tell them our cell phones died.” “Our phones don’t have a signal out here.” Fucking cell phones! Horror movies are always out of network!) But Duncan was excited to do this and reach a new generation of readers so while I don’t think it’s absolutely necessary, I don’t mind it too much.

(I wish she had updated some of the sexism and fat shaming though.....)
Profile Image for Diego Sanchez.
88 reviews37 followers
July 26, 2017
3.5 stars

As plenty of you, I know this movie since I think it is one of the most representatives from the 90's and one of my favorites may I say, since it has an iconic cast and I found it fun and suspenseful as well. Sadly, if you are looking to see the movie turning into a book you will be wrong (As me) and here are my thoughts:

*Plot/Development: This book tells us the story of four teenagers who are involved in an accident, that ends up wrong since it turns for them to kill someone. Months later, Julie receives a letter with “I know what you did last summer” written on it and by then, everything changes.
Honestly, the plot is always there, you will found it in every chapter and each one of the character is “tortured” in different ways, so that causes the students to create changes in their way of seeing their lives. The Development is a page turner, but I think it is very predictable since the middle of the book, at least for me, even though I read it till the end because I wanted to know what would happen.

*Characters: With four main characters (two boys and two girls), it was amazing the fact that they had this oldie vibe and even when they are the cliché personalities (Good, Bad, Innocent, Silly, Handsome, Pretty, etc.) I found it interesting and I think this can be passed on because of the time it was written. As for the secondary characters, all of them play an important role: Parents changing situations and Friends creating gossips.

*Genre: This is a YA Mystery which plays very good with it, I recommend it for the people who wants to get introduced in this genre and love the old vibes. It is not scary at all and if you love cheesy movies or books, this one would be your choice.

*Ending: As I said previously, was predictable since the middle of the book for me, but for certain reasons, I enjoyed how it ends, not because it was the best ending, but because of the resolution and conclusion of ideas that were presented at the beginning. Could be an open ending, but based on the time that was written, it is an ending that could be totally inferred.

*Writing: I read the second version of the book, which was re-written, so there is no other more to say that you will be reading a classic writing with “new” fashion vocabulary.

As an extra, I loved the reader questions and the Q&A with the author, because my doubts about the film were solved.

Favorite Character: Helen
Favorite Quote: "If you can't run away", Julie said Chokingly, "What can you do?"
"Face up to it"
Profile Image for Misty's Book Space.
964 reviews47 followers
August 1, 2020
2.5 Stars


I came across this book sometime last year at a library book sale. I didn't know this was a book. I watched the movie a long time ago and I've watched it several times since then. When I saw this at my local library I decided to get it because I actually really liked the movie and I assumed I would enjoy the book just as much if not more. Unfortunately that wasn't the case for this book.

As I mentioned above I watched the movie long before I ever read the book so its possible that if I had done it the other way around I would have actually really enjoyed the book. I was expecting this to be pretty similar to the movie but it was completely different.

I can't really get into all the details of everything that's different without spoiling the whole book so this is going to be a hard one to review. Most of the characters were so annoying. Even though I watched the movie and knew how it was going to end because of all the changes I didn't know the who did it aspect but it was all very predictable. It's classified as a suspense thriller and to me the suspense was severely lacking.

I know this review makes absolutely no sense but I just don't know what to say about it. I think the only reason I even continued reading this book was because I had seen the movie and loved it.
Profile Image for Ashley Daviau.
2,135 reviews1,026 followers
March 7, 2021
I’ve been a huge fan of the movie based off this book for YEARS so imagine my surprise when I found out it was based on a book. I truly had no idea and when I found out I knew I had to read it! While I did enjoy it, I don’t think it’s anywhere near as good as the movie and I was a little disappointed. I rarely find the movie is better so I was surprised to find myself feeling that way after finishing the book. It does still remain an excellent book and I just tore through it but it was missing that little something extra to make me fall fully in love. It’s a great story and I’ll never not love it, whether in book or movie form!
Profile Image for Benji's Books.
422 reviews5 followers
April 18, 2024
A well-written YA mystery that I only just realized was a 1975 book before the 1997 slasher. The book is not so much a slasher as its adaptation made it into, but more of a slow-burn mystery.

I read the original, unedited story, before the author made some adjustments, like adding the internet and texting in, among a few other additions.
Profile Image for Tom.
199 reviews54 followers
July 29, 2022
If you're going into this having seen the movie adaptation, hoping to read all about big-breasted beauties battling hook-handed maniacs, then prepare to be a little underwhelmed. Lois Duncan's I Know What You Did Last Summer is more like Betty Ren Wright cut with Shirley Jackson, with a side of Robert Blochian bait-and-switch (I'm still not over Psycho II , btw), than the "Scream"-influenced slasher. In fact, Duncan hated what Hollywood did to her story, not least because of her own traumatic experience as the mother of a murder victim. This original version is mild, well-written stuff. I'd be concerned if it was anyone's favourite book but it's good for what it is.
Profile Image for Valery Tikappa.
1,010 reviews539 followers
September 23, 2021
Con questo libro spunto la casella della Fuffy Reading Challenge: le cinque leggende, un libro a tema con una festività.
https://www.instagram.com/p/CJa82pnre_K/

So cosa hai fatto è il libro che ha ispirato l'omonimo film cult degli anni '90: quattro ragazzi hanno un terribile segreto riguardante una cosa che hanno fatto una notte d'estate. Sembrano quasi averlo dimenticato se non fosse che cominciano a ricevere degli strani messaggi... che il loro segreto stia tornando a galla? Da chi? E perchè proprio ora?

Da amante degli horror avevo già visto So cosa hai fatto ma non avevo idea fosse la trasposizione cinematografica di un libro quindi quando l'ho iniziato ero felicissima di poter rivivere le stesse sensazioni del film nel modo che preferisco: a parole.

Il libro, infatti, mi è piaciuto. è stata una lettura piacevolissima, un ritorno agli anni '90... ma, ahimè, niente di più.
Sarà che conta a stento 200 pagine ma ho trovato la caratterizzazione dei personaggi un po' povera; non nel senso che sono macchiette nella storia, ma sono superficiali. Caricature più che personaggi. Caratteri più che caratterizzati.
In questo secondo me il libro perde molto.
Avrei preferito più approfondimento piuttosto che mera descrizione di scene.

Bisogna anche tenere a mente che è un libro scritto nel 1973, quindi ci sta che la narratività sia diversa rispetto a quella di oggi, ma d'altro canto penso a libri di quegli stessi anni che ho apprezzato decisamente di più e quindi un po' ne sono rimasta delusa.

La trama di fondo comunque è sempre riuscitissima per me, nonostante sia prevedibile il colpevole (che voi abbiate visto il film o meno).
Non so, comunque, se lo definirei young adult. Sì, i protagonisti sono adolescenti, ma mancano tutte le tematiche che fanno dello YA, beh... lo YA.

In ogni caso è stato bello fare un tuffo negli anni 90, quello è sempre apprezzatissimo!
Profile Image for Samichtime.
425 reviews5 followers
October 2, 2024
Solid tale and different enough from the movie to make it interesting! 😸🍿
Profile Image for Claude's Bookzone.
1,551 reviews260 followers
July 23, 2020
I really wish there had been a lot more tension in this story. It's quite a short book so there was definitely room to add some more scary scenes. I feel like the movie may have been an improvement on the original idea, which is actually a really good one, but given it scored 5.7 on IMDB that's not saying a lot. Great premise, underwhelming delivery.
Profile Image for Becca.
805 reviews77 followers
August 25, 2020
There are A LOT of issues with this book that made me cringe, especially after finding out that Lois Duncan actually went in and updated some of the story, but didn’t update scenes that really could have used the updating.

Also. It’s boring. & all of the characters were horrible. I said what I said. 🤷‍♀️
Profile Image for Simona.
679 reviews62 followers
July 28, 2022
Man that was not as I hoped
Profile Image for Devoralibros.
279 reviews53 followers
May 5, 2022
▪️Julie, Ray, Helen y Barry, cuatro adolescentes que tras una fiesta tienen un accidente de coche llevándose por delante la vida de un niño. En vez de auxiliarle, huyen por el miedo a la condena que les pueda caer que hará que arruine sus vidas.

▪️Un año después, empieza a suceder una serie de hechos que les demostrará que no son los únicos que saben qué hicieron el último verano.

▪️¿Quién no conoce esta historia? Yo, personalmente, la conocía por la película la cuál vi en el cine en su momento y es de esas películas de terror que son difíciles de olvidar. El libro está muy bien escrito y su lectura es muy ágil, apenas me lo he leído en unas horas y la tensión está garantizada casi desde el inicio hasta el final. Al principio me costó sacar de mi cabeza las imágenes de la película y poder centrarme únicamente en el libro, pero conforme fui avanzando, comprobé la cantidad de diferencias que hay con la película. Sí, la trama principal es casi la misma, pero nada más y es lo que más me ha gustado, que sea diferente y no me esperara ese final. Lo que deja bien claro es, que no podemos huir de nuestro pasado; tarde o temprano vuelve y habrá que afrontar cualquier acto que cometimos y no solucionamos en aquel momento.
Profile Image for nico.
90 reviews13 followers
August 14, 2024
I just felt like something was missing. if you’re expecting it to be a slasher just like the film, you are mistaken. it’s a suspense novel.
Profile Image for ChunderHog.
28 reviews
August 8, 2009
!!WARNING THIS WARNING CONTAINS A SPOILER THAT THIS BOOK WAS MADE INTO A MOVIE.!!

Hopefully you didn't just read that. For those of you who were smart enough to skip that spoiler you can now read in confidence knowing that you will not be told that the book was made into a movie. You will live in happy naivety thinking that the book is a self-contained form of media in which this narrative lives. Unfortunately, you will be wrong.

Since I have neither read the book, nor seen the movie. I can safely say that I am an objective critic when it comes to comparing the book to the movie. At this point I rate them dead even. Their titles are exactly the same and I have mild interest in finding out what occurred last summer in either format. In the movie I will expect great special effects and bad acting. In the book I will expect suspense and action emphasized at the expense of thematic meaning. The problem with comparing books and movies is that one tends to regard the version one experienced first as the gold standard. To avoid this I plan on reading the book and watching the movie at the same time. If I get too far ahead in the movie compared to the book, however, it will be the same as watching the movie first, so I plan on finishing the two simultaneously. I will accomplish this by enrolling in a speed reading course and by watching the movie on my old VCR that seems to be running at 1/4 speed.

Everybody wish me luck! I'll update with results as I get them.
Profile Image for Erin *Proud Book Hoarder*.
2,764 reviews1,167 followers
January 27, 2016
I've found that I love Lois Duncan's writing style, her stories, and her hidden layers, but this one fell a bit short. It's ironic since out of the stories I've read of hers, this is inferior, but it's the most popular because of the movie.

The film, by the way, is much different. We don't get a hand hook killer tracking down the teenagers. Here it's a mini mystery. The ending is rather simple and cheesy. Backstory is depressing, you feel for the victim and the consequences. I liked the main character and her personality shone through pretty well. Since the pool of possibilities is narrow, the villain isn't a huge surprise. I dug the twist about the flowers and it's false impressions, painting a potential hero as the ultimate enemy.

Tension is present, although nothing heart-pounding. There's little gore and a lower body count than the movie. As with the film, the sister of a character is unlikeable, maybe even more so in written form. The book is short so the pacing is fast, but there's not much space to draw anything out or dig too deeply into characterization.

The opening of the book was interesting enough, although the center was the most rewarding, as it was going in different directions and actually building something. Even with the ending being an anticlimactic rush, it's a passable book, even if it's not one of Duncan's best.
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