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 Guthrie, his girlfriend Sam Lane, virgin Sara Parkington, her boyfriend Doug Bell, socially awkward Jimmy Mortimer, and jokester Ted Cooper. 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 get revenge for the murder of his sister.
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 though 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 only for Jason to drive a double-bit axe through her chest.
Worried for Tommy's safety, Trish and Rob return to the house. They then 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.
- Ted White as Jason Voorhees (uncredited)
- Kimberly Beck as Trish Jarvis
- Corey Feldman as Tommy Jarvis
- Erich Anderson as Rob Dier
- Joan Freeman as Mrs. Jarvis
- Barbara Howard as Sarah
- Peter Barton as Doug
- Judie Aronson as Samantha
- Alan Hayes as Paul
- Crispin Glover as Jimmy
- Camilla More as Tina
- Carey More as Terri
- Lawrence Monoson as Ted
- Bruce Mahler as Axel
- Lisa Freeman as Nurse Robbie Morgan
- Bonnie Hellman as Hitchhinker
When Friday the 13th Part III was released, it was initially supposed to end the series as a trilogy, however there was no moniker to indicate it as such. In 1983, there were rumors that Paramount Pictures billed the fourth film as "The Final Chapter" as a result of them feeling embarrassed by their association with the series. Despite how Roger Ebert and Gene Siskel claimed this in their review of the film on At the Movies, Paramount Pictures was aware that the slasher genre had been declining in interest. However, the idea came from producer Frank Mancuso, Jr. (the son of Paramount CEO Frank Mancuso, Sr.) as he began to resent the series due to how he felt nobody respected him for working on Friday the 13th Part 2 as a production assistant and Part III as producer, regardless of how much money the films earned. As a result of this and him wanting to work on different projects, he wanted to conclude the series by killing off Jason.
The filmmakers wanted Joseph Zito, who had previously worked on The Prowler, to direct and write the screenplay for the film. He initially claimed that he wasn't a writer, but he later accepted it when the contract offered him double payment for directing and writing. Zito secretly used the extra salary to hire Barney Cohen to write the script. Their process entailed Zito taking one-hour phone calls every night with Phil Scuderi to discuss the film's screenplay and story. He then met Cohen in a New York apartment to use the ideas Scuderi had offered, which then they would turn into script pages sent that day to Scuderi in Boston to be discussed again over the phone. Cohen remained credited for writing the film, but Zito and Cohen eventually got into trouble with the Writer's Guild of America as a result.
Previous Friday the 13th films generally favored young women being the final girl. However, this is the first film in the series to not only have two survivors instead of one, but one of them being a child. The filmmakers believed this aspect has never been done before in a slasher film, as well as them wanting to create characters that the audience don't want to see harmed or killed. By including the Jarvis family (a divorced mother, a teenage daughter, and a pre-teen son) opposite the usual cast of teenagers, they could generate more drama and resonant tragedy such the implication of Mrs. Jarvis killed outside by Jason, and thus remaining debatable how intentional the parallels are between Jason and Tommy. Tommy's interest in make-up effects served as an homage to Tom Savini.
Camilla More initially auditioned for Samantha, but when the filmmakers discovered she had a twin sister they were instead offered the roles of Tina and Terri. Amy Steel, who starred as heroine Ginny Field in Friday the 13th Part 2, co-starred with Peter Barton on the sitcom The Powers of Matthew Star. Barton was offered the role of Doug when the sitcom was cancelled, but he was initially reluctant as he wanted no part in any horror film, especially after he disliked working on Hell Night. However, because Steel was involved in Part 2, she talked him into doing the film.
Make-up artist Tom Savini, who had not returned for Part 2 and Part III, agreed to work on the film to help kill off Jason, who he helped create in the original film.
Filming commenced in October 1983 to January 1984 in Topanga Canyon and Newhall, California, 6 weeks over-schedule. It was originally set to be released in October 1984, but Frank Mancuso, Sr. pushed the release date to April 13, leaving them 6 weeks to complete post-production. The only time Paramount helped with the film's production, they rented a house in Malibu for the filmmakers to stay and conduct editing sessions, with food brought to them by the studio.
The film had a troubled production on set. As a result of the director's poor treatment and the film's budget, many of the actors had to perform uncomfortable or dangerous stunts for the movie. Judie Aronson was required to remain submerged in a highly freezing lake, in which she later developed hypothermia because of it, and Peter Barton was genuinely slammed against the shower wall when Jason attacks him. Ted White, who portrays Jason Voorhees, defended several of the actors by requesting Barton to have a crash pad, and threatening to quit when Zito refused to remove Aronson from the cold lake in-between takes. White and Zito maintained a hostile relationship on set, resulting in White demanding his name to be removed from the credits. According to White, Corey Feldman maintained a bratty attitude on set as a result from Zito's treatment. When filming the scene of Tommy hacking at Jason's body, which were two sandbags he was striking at, Feldman pretended the sandbags were Zito.
According to the book Crystal Lake Memories: The Complete History of Friday the 13th, actress Kimberly Beck stated that she does not like the horror genre. In addition to this, she felt that the film was more of a C-movie rather than a B-movie. During filming, Kimberly Beck experienced strange encounters, including a man watching her while she ran in the park and receiving odd phone calls at all hours. This stopped when production was finished.
Actress Bonnie Hellman's agents told her she would not want to take the role of the hitchhiker in the film as there were no lines for the character, but she accepted the role anyway.
The film's music was composed by Harry Manfredini, who composed the scores to all of the series' previous installments. On January 13, 2012, La-La Land Records released a limited edition 6-CD boxset containing Manfredini's scores from the first six entries of the film series. The release was sold out in less than 24 hours of availability.
The song "Love Is a Lie" by Lion is featured in the film, but not on the soundtrack.
On the review aggregator website Rotten Tomatoes, Friday the 13th: The Final Chapter holds a 20% approval rating based on 30 reviews, with an average rating of 4.19/10. The consensus reads: “As lumberingly single-minded as its homicidal star, Friday the 13th - The Final Chapter adds another rote entry to an increasingly labored franchise.” Roger Ebert and Gene Siskel berated the film on their show, with the former deeming it "an immoral and reprehensible piece of trash."
Scott Meslow summarized Roger Ebert's criticism as calling it "a cynical retread" of the earlier films, noting that the film instead attempts to kill off the series while focusing more on characterization than gore. In a series retrospective, Kyle Anderson of Entertainment Weekly ranked it the best Friday the 13th film, complimenting both its narrative and kills.