Helen (Sarah Michelle Geller) and Julie (Jennifer Love Hewitt) and their boyfriends Barry (Ryan Phillippe) and Ray (Freddie Prinze Jr.) are enjoying their post-graduation summer in their small North Carolina hometown. They are the most unbelievably expressive and erudite teens you'll ever meet (unless you live near Dawson's Creek) -- "I understand your pain," they tell each other in dead earnestness. But they panic when late one night, driving home on a twisting road from a beach party, they hit a man crossing the dark road. Not wanting to ruin their chances at college and the charmed lives they are of course destined for, they dump the body in the ocean and drive off.

Cut to a year later. Helen has bombed out of her go at being a New York actress and is back home working in the family department store. Julie returns from college, ashamed that she is flunking out. Ray, now working as a fisherman, laments that he has turned into his father. Barry is an even bigger jerk than he was a year earlier. They're all getting on each other's nerves and can't seem to pick up their friendships where they left off.

Ah, how the dreams of our youth get crushed when we meet reality. If only our grades had been better, if only we'd worked harder, if only we hadn't committed that murder. See, there's a note waiting for Julie at home: "I know what you did last summer." And someone is stalking the four reunited friends, playing nasty practical jokes like leaving dead bodies around for them to find.

So, like Nancy Drew and her best friend George, Julie and Helen set out to find the stalker, who follows them around wearing a fisherman's slicker and hat. Think The Secret of the Gorton's Fisherman or The Mystery of the Ice Hook. Or picture Velma and Daphne pulling the mask off the villain to reveal the creepy amusement park owner. Not scary, and not even particularly funny.

The biggest mystery of I Know What You Did Last Summer -- and it remains unsolved -- is this one: Why on Earth does Julie (who supposed comes from money) drive around this flick in an incredibly uncool Plymouth K car?