I KNOW WHAT YOU DID LAST SUMMER: How The 20-Year-Old Horror Film Created An R-Rated Nancy Drew

The classic teen slasher turns 20 today.

I was 16 years old when my friends and I rolled six deep to the movie theater to watch the latest teen slasher movie. For my friends, that’s all I Know What You Did Last Summer was: just another slasher to hold us over until the next Scream came out (and we loved Scream less than a year earlier). But for me, my enthusiasm came with a caveat. I was miffed by the fact that all the trailers showed a darker, bloodier narrative that looked in no way similar to Lois Duncan’s 1973 YA mystery novel upon which it was based. It seemed gratuitous and dumbed down for presumably an audience that the director Jill Gillespie and screenwriter Kevin Williamson didn’t think could handle something more intellectual. But I soon discovered that there is something special about this movie that doubled down on crop tops and gore. I Know What You Did Last Summer still manages to gives its young female protagonist (played by Jennifer Love Hewitt) the authority to be her own hero in the face of unspeakable horror, and simultaneously present her as a deeply flawed heroine with a killer past. Not to mention, the movie kick started a gripping new horror franchise that dared to distinguish itself from its literary origin—and still haunts us 20 years later.

A hooded villain with a hook for a hand may not seem frightening to those coming up in a more technologically sophisticated era of CGI and cool special effects on the big screen. But back then, fans were—and remain—unsettled by the fact that this particular bad guy was completely mysterious though he was not hiding behind a mask like so many other famous boogeymen before him. This meant our imaginations ran wild. We see a man slashing throats, creeping into homes in the middle of the night, and terrorizing teens like myself at the time—and right away we put him right up there with the greats. But what’s clever about the movie is that its protagonist is not so innocent herself, and while we may want to condemn her in the beginning—when she and her friends run over a man on the road and carelessly toss his body into the sea—we find ourselves rooting for her instead. We so easily fall into advocating for a young woman desperate to put behind her a past that has literally come back to stalk her and her crew. Maybe because this veiled villain is so scary, or maybe because we see something about her, a young woman on the cusp of college and adulthood, that makes us want her to win. Or maybe it’s because tries to protect her friends and seems to be a genuinely good person—despite the whole hit-and-run-thing.

Regardless, she’s a victim who’s first terrorized by cryptic chain letters from someone who saw what she and her friends did to that poor man late one night (for younger readers, chain letters were kind of like evil tweets from someone with an egg avatar.). Then her friends are offed one by one. But instead of going to the police about it, and outing what they did, she attempts to control the situation and take matters into her own hands. In doing so, she sort of becomes a '90s version of Nancy Drew, trying to interpret the clues and solve the murders—and prevent her own—with low-rise jeans, biting one-liners (thanks to Julie’s doomed pal Helen, played by Sarah Michelle Gellar), and one brooding yet charming ex-boyfriend (played by Freddie Prinze Jr), with whom she reconnects for the first time since their fateful evening the summer before.

So in a way, I Know What You Did Last Summer does reconcile with the fact that it comes from a YA novel. But the tone is much darker, earning every ounce of its R-rated status. Julie may not have the squeaky clean image of Nancy Drew, or her slick gumshoe tactics, but she has her fierce determination. Her motivation, however, is radically different from the iconic character. Julie is driven by a need to keep buried something she is deeply ashamed of, for which she is willing to risk her own life rather than go to the police. That intense fear of being found out, of it being exposed that she’s not the perfect girl everyone thought she was is more tantamount to her than anything else. And that is so indicative of pretty much everyone’s high school experience. You saw that most profoundly in Julie’s character. But you also saw that with Helen, the popular homecoming queen whose hair the killer cut off in her sleep, a violation more horrifying to her than the fact that an actual lunatic walked into her home in the middle of the night with a weapon. 

Julie is at her most frantic about three-quarters into the film when she still isn’t able to identify who’s been stalking them, so she runs into the middle of the street and yells at the sky: “What are you waiting for?!” It’s a moment in the film that’s become iconic in some circles. It's the first time she seems defeated, like she is ready to end this exhausting chase even if it means risking her life. She is tired of not being able to speak about the incident with her friends and she is also tired of looking for someone who is clearly too clever to be found out.

I Know What You Did Last Summer went on to birth two additional sequels—I Still Know What You Did Last Summer and I’ll Always Know What You Did Last Summer (which we don’t ever speak of, with good reason). It’s a movie that further proves a film doesn’t have to be identical to the book from which it derives, and also makes an important statement about the complexity of heroism in female characters that still resonates today.