After four high school friends are involved in a hit-and-run road accident, they dispose of the body and vow to keep the incident a secret. A year later, they each start receiving anonymous letters bearing the warning "I Know What You Did Last Summer."
Ever since killing the Fisherman one year ago, Julie James is still haunted by images of him after her. When her best friend Karla wins free tickets to the Bahamas, Julie finds this a perfect opportunity to finally relax. But someone is waiting for her. Someone who she thought was dead. Someone who is out again for revenge.
It's graduation day at Huntington Hills High, and you know what that means - time to party. And not just any party, either. This one will be a night to remember, as the nerds become studs, the jocks are humiliated, and freshman crushes blossom into grown-up romance.