The film was written and directed by Tom McLoughlin and its original concept called for Tommy Jarvis, the protagonist of parts IV and V, to become the new villain, unfortunately the poor fan reception of Friday the 13th Part V: A New Beginning prompted the producers to bring back Jason Voorhees as the series’ antagonist. In resurrecting Jason, McLoughlin made Jason an explicitly supernatural force for the first time in the series, depicting him as being raised from the dead via electricity; this version of Jason, an undead serial killer and more powerful superhuman, would become the standard depiction for the rest of the franchise, until 2009’s remake.
Years have passed since Crystal Lake had been renamed to Forest Green, but Tommy Jarvis, still suffering from hallucinations, returns with Allen, a friend from the hospital in Part V, hoping to cremate Jason’s body and stop his hallucinations. At the cemetery, they dig up Jason’s corpse, but seeing it causes Tommy to snap, and he stabs Jason’s body with a metal fence post. As he turns his back on Jason, two lightning bolts strike the post and revive the now-undead killer. Tommy tries to light the gasoline in which he has soaked Jason, but a sudden downpour prevents it. When Hawes tries to attack Jason with a shovel, his heart is punched out. Tommy runs and makes his way to the sheriff’s office, where his panic and attempt to grab weapons gets him put into a jail cell. His pleas that Jason has returned goes unheeded by Sheriff Garris. On the road, two young adults, Darren and Lizbeth get lost looking for the camp and run into Jason, they fail to frighten Jason off the road and he impales them both with the metal rod that resurrected him. The next morning, Garris’ daughter Megan and her friends Sissy, Cort and Lizbeth’s sister Paula ask him to search for Darren and Lizbeth. Tommy warns them about Jason, but as he is now considered an urban legend they ignore the warnings, though Megan finds herself attracted to him.
In the woods, Jason happens upon a corporate paintball game, he kills four of them for their equipment and chases the helpless, clumsy Roy off into the woods. At Camp Forest Green, the kids arrive, and the teens do their best to run the camp without Darren and Lizbeth. Meanwhile, Garris decides to escort Tommy out of his jurisdiction due to his influence on his daughter, Tommy tries to make a run for Jason’s grave, but finds that the caretaker had covered it up to deny responsibility for it being dug up, and Hawes’ body is buried in its place. Tommy is then escorted out of town. Cort goes out to have sex with a girl named Nikki, who borrowed an RV from her step-father, when the power is pulled suddenly, they vacate the area, unaware that Jason had snuck on board. He crushes Nikki’s skull then kills Cort by ramming a bowie knife into his skull. He then happens upon the caretaker and stabs his throat out with his own whiskey bottle, then kills a nearby couple who happened to witness the murder. The sheriff’s men discover several dead bodies and Garris immediately implicates Tommy in the murders, meanwhile Tommy has contacted Megan and convinced her to help him exorcise Jason back into the lake he drowned as a child. Jason makes his way to the camp and frightens one of the children, Nancy. Paula and Sissy show her there is nothing to fear and send her to bed, when Paula falls asleep, Sissy is grabbed through their cabin window and her head is twisted off. Nancy again sees Paula and shows her a bloodied machete. Convinced Sissy and Cort are playing pranks on each other, they go out to find them.
Meanwhile, Megan and Tommy are pulled over by Garris, and despite her alibi she was with him, he does not believe Tommy to be innocent and they go out to the camp to investigate. Tommy and Megan develop a ruse to trick the deputy and they both escape the station together. At the camp, Jason slaughters Paula after she put Nancy to bed and the police arrive to investigate, discovering the carnage, Jason quickly takes out both of Garris’ men. When Megan arrives, her calls to her father alert Jason who tries to go after her. Garris confronts Jason and shoots him several times, but to no avail. When Garris shoots Jason in the head, he realizes Tommy was telling the truth. Jason kills him by bending him in half. Jason is about to kill Megan, but Tommy calls to him from the lake, and he goes after him instead. Tommy is attacked in the boat in the middle of the lake, and ties a boulder around Jason’s neck, but he fights back, holding Tommy underwater long enough to drown him. Megan rushes out to save him and is nearly killed herself when Jason grabs her leg, she turns the boat’s motor into Jason’s neck and he releases her. She takes Tommy back to shore and uses CPR to revive him. Tommy laments that it is finally over, and that Jason is home.
Under the water, tied in a prison at the bottom of the lake, Jason stares patiently off into the water, glaring at the audience as the screen fades to black.