Description
The night after the events at Higgins Haven, police clean up the grounds and Jason Voorhees's body, believed to be dead, is taken to the morgue. At the hospital, Jason spontaneously revives and escapes from the cold storage, murdering the coroner Axel Burns with a hacksaw and gutting Nurse Robbie Morgan with a scalpel. The following day, a group of teenagers drive to Crystal Lake for the weekend. The group consists of Paul, his girlfriend Sam, virgin Sara, her boyfriend Doug, awkward Jimmy, and jokester Ted. On the way, the group comes across Pamela Voorhees's tombstone and a hitchhiker, who is soon killed by Jason.
The teens arrive and meet neighbors Trish Jarvis, her twelve-year-old brother Tommy, and the family dog Gordon. While going for a walk the next day, the teens meet twin sisters Tina and Terri Moore, and go skinny dipping with them. Trish and Tommy happen upon the scene, and Trish is invited to a party taking place that night. Afterwards, when their car breaks down, Trish and Tommy are helped out by a young man named Rob Dier. They take him to their house, where he meets their mother and Tommy shows him several monster masks he made himself before Rob leaves to go camping.
Later that night, the teens begin the party. A jealous Sam sees Tina flirting with Paul and leaves. She goes out to the lake where Jason impales her with a spear from under a raft. When Paul goes out to look for her, he is stabbed in the groin with a harpoon gun. Terri tries to leave the party early, but before she can get on her bike Jason stabs her with a spear. Mrs. Jarvis arrives home and discovers the power outage. While searching for her children and Gordon, she is killed offscreen. Trish and Tommy soon arrive and realize their mother is missing. Trish goes to search for her and finds Rob's campsite. It is revealed that Rob is actually the brother of Jason's victim Sandra Dier from the second installment. Rob further explains to her that Jason is still alive and he came to Crystal Lake to avenge his sister's death. Worried for Tommy's safety, Trish and Rob return to the house.
After sleeping with Tina, Jimmy goes downstairs to get a bottle of wine. Jason pins his hand with a corkscrew before striking him in the face with a meat cleaver. Tina looks out a window upstairs and finds that her sister's bike is still there. Jason then bursts through the window and throws her to her death, crashing on the car. While a stoned Ted watches stag films with a film projector, he gets too close to the projector screen and is stabbed in the head with a kitchen knife from the other side. Jason then goes upstairs where Doug and Sara finish making love in the shower. After Sara leaves, Jason kills Doug by crushing his head against the shower tile. When Sara screams upon finding Doug's body, she tries to escape but gets a double-bit axe through her chest.
Trish and Rob go next door to investigate and discover the teens' bodies. Gordon flees, and Rob is killed by Jason in the basement as Trish runs home, taking Rob's machete with her. She and Tommy barricade the house, but Jason breaks in and chases them into Tommy's room. Trish lures Jason out of the house and escapes, then returns home and is devastated to learn that Tommy didn't run away. She senses Jason behind her and tries to fight him off with the machete but is overpowered. Tommy, having disguised himself to look like Jason as a child, distracts him long enough for Trish to hit him with the machete, but she merely whacks off his mask. As Trish stands horrified at Jason's deformed face, Tommy takes the machete and strikes it in the side of his skull, causing him to collapse to the floor and split his head upon impact. When Tommy notices that Jason's fingers are slightly moving, he continues to hack at his body screaming, "Die! Die!" while Trish repeatedly yells out his name.
At the hospital, Trish is visited by Tommy. He rushes in, embraces her, and gives a disturbed look while staring into the camera.
