After the hit-and-run accident, the four friends - Julie, Ray, Helen, and Barry - make a pact to keep the incident a secret. They resume their lives, with Julie attending college and the others staying in their hometown and adapting to adult life. However, their secret is threatened when a mysterious figure starts sending them letters, reminding them of the accident and urging them to come clean.
As the letters become more frequent and threatening, the friends start to unravel. Julie seeks help from Ray, her former boyfriend who is now a fisherman, but he's hesitant to reopen old wounds. Helen, a budding actress, becomes increasingly paranoid and isolated, believing that the stalker is after her. Barry, a hot-headed athlete, takes matters into his own hands and starts a dangerous game of cat and mouse with the stalker.
As the friends dig deeper into the mystery of the letters, they uncover a shocking truth about the hit-and-run accident. They realize that they may be in much more danger than they originally thought and that their secrets may have grave consequences.
The tension builds as the stalker closes in on the friends, leading to a climactic showdown on the Fourth of July, one year after the accident. In the end, the truth about the accident is revealed, and the friends come face-to-face with the stalker, who turns out to be someone they never expected.