"I Know What You Did Last Summer" is a 1997 slasher film about four teenage friends—Julie James, Ray Bronson, Helen Shivers, and Barry Cox—who accidentally hit a man with their car while driving home from a beach celebration. Believing they have killed him, they dump his body into the water and vow never to speak of the incident. A year later, Julie returns home from college and starts receiving threatening messages saying, "I Know What You Did Last Summer." The group is then stalked and attacked by a mysterious figure wielding a hook, who turns out to be the man they thought they had killed, seeking revenge. The story unfolds with mystery, suspense, and a series of violent encounters tied to their dark secret.

There is also a 2025 film continuation set 27 years after the original murders, where a new group of friends encounters a similar deadly stalking and uncover new secrets related to the original event.