How I Know What You Did Last Summer's Author Really Feels About The Movie

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Jim Gillespie's 1997 slasher movie "I Know What You Did Last Summer" was the first high-profile slasher to come out after the success of "Scream," which came out less than a year earlier. Both films were written by Kevin Williamson, so they had a similar vibe, but "IKWYDLS" was a clear indicator that a trend had begun. Slashers were back, baby. 

The slasher premise of "Last Summer" is simple. A quartet of pretty young people — Jennifer Love Hewitt, Ryan Philippe, Sarah Michelle Gellar, and Freddie Prinze, Jr. — accidentally run over a vagrant in their car one summer, killing him. Rather than call for help, they dump the body and swear each other to secrecy. Oh yes, and they gave him a few thwacks on the way to the ocean, pretty much actively murdering him. Fast-forward to the next summer, and the quartet is racked by guilt. When reunited, they receive a mysterious note with the title of the film written on it. Is someone watching them? Shortly thereafter, a masked assailant in a fisherman's slicker begins murdering them, one by one, with an outsize fishhook. 

The only problem with this premise is that "I Know What You Did Last Summer" was never intended to be a slasher. The film was based, rather loosely, on the 1973 YA novel by Lois Duncan. Duncan also authored the novels that inspired the movies "Hotel for Dogs," "Summer of Fear," "Killing Mr. Griffin," and the very similar "Teaching Mrs. Tingle." Her "Last Summer" novel begins the same way as Gillespie's movie, but the murderous fisherman and the slasher elements were all invented by Kevin Williamson. 

In Clark Collis' upcoming interview book "Screaming and Conjuring: The Resurrection and Unstoppable Rise of the Modern Horror Movie," the writer quotes an interview with the late Lois Duncan, and she was horrified to learn that her book had been turned into a murder spree. She would have never advocated for such violence, especially after she lost her daughter to a murderer. 

Lois Duncan published her first novel, "Love Song for Joyce," in 1958 and remained prolific throughout her career. "I Know What You Did Last Summer" was novel number 14, and by then, she had recognized a pattern in her own work; she typically told stories of young women in peril. The original "IKWYDLS" novel begins with the same quartet of teens, but their unintended hit-and-run victim was a young boy on a bicycle. They, too, cover up the death and grow guilty and despondent over the course of the next year. The rest of the novel involves a long series of notes, indicating that someone knows what they did last summer. Barry gets shot in the stomach at some point, but he pulls through, and Julie gets strangled, but she is rescued. There are no actual murders. Duncan's book isn't a slasher, but a tragic mystery. 

In 1989, Duncan's youngest daughter, Kaitlyn Arquette, was murdered in New Mexico. She was only 18. The case was cold for the rest of Duncan's life, and she turned away from writing violent stories of women in peril. She petitioned repeatedly to keep the case open. Duncan passed in 2016, and Arquette's murderer wasn't found and indicted until 2022. Duncan, when asked about the 1997 adaptation of her work in 2010, said she was appalled by the violence. Her exact quote:

"It was my characters and my plot gimmick, but then it went in all directions. I was quite horrified by the sensationalized violence. Several years earlier, my own teenage daughter, Kait, had been chased down in her car and shot to death, and I had seen, right in front of my eyes, what real violence is. To have people screaming and laughing about it did not go down well ... So I was not happy with the movie."

Understandable. 

While Duncan wasn't fond of the violence, especially in light of her real-life tragedy, she was pleased that Gillespie's "I Know What You Did Last Summer" was a success. She was pleased to see that her original novel was being purchased again, as were many of her other works. In her words: 

"I have to admit I was happy with the fact that the book had been made into a movie, because that made all my backlist suddenly very popular. It was like getting a rebirth, but in a very strange way."

And if the popularity of the "I Know What You Did Last Summer" forced the police to pay closer attention to Duncan's daughter's case, then it may have been worth it. The book was eventually rewritten and re-released in 2010, this time with updated references and technology. The story was the same, but the characters all had cell phones now, and one character was now an Iraq War vet, not a Vietnam vet. 

Meanwhile, the movie version of "I Know What You Did Last Summer" was popular enough to warrant several follow-up projects. "I Still Know What You Did Last Summer" was released in theaters in 1998, and "I'll Always Know What You Did Last Summer" came out straight-to-video in 2006. An eight-episode reboot TV series, also called "I Know What You Did Last Summer," was released on Prime Video in 2021. 

Now playing in theaters is a direct sequel to the 1997 and 1998 movies, frustratingly also called "I Know What You Did Last Summer." The new film reunites the surviving characters from the first movie, but is told mostly from the perspective of a new generation of hot youngsters. It, too, is a slasher, though, so Lois Duncan may not have liked it.