Maniac is a 1980 American slasher film (though considered more of a splatter film), about a disturbed and traumatized serial killer who scalps his victims. It was directed by William Lustig, and co-written by Joe Spinell (who also developed the story and starred as the lead character) and C.A. Rosenberg.
Frank Zito is a middle-aged, overweight man living in an unspecified borough of New York City, possibly The Bronx, Staten Island or Brooklyn. Frank works as the janitor of an apartment building, a detail revealed only through the presence of keys displayed upon a corkboard beside his apartment door. At night, his personality degenerates into that of a mumbling schizophrenic, who carries on one-sided, often incoherent conversations with his dead mother while stalking around a small bedroom filled with hacked-up mannequins and childhood mementos. As the film progresses, the audience becomes privy to Frank's nighttime stalking sessions, in which he ventures into the city to kill and scalp women. Frank then brings their scalps back home to nail to mannequins, which he then sleeps with for several nights before placing the mannequin in another area of his apartment and going out again to repeat the process.
Midway through the film, Frank befriends and then romances a fashion photographer, but his daytime life and nighttime life begin to merge, to the point that he loses his tenuous grip on reality altogether. The film's now infamous ending finds Frank's mannequins transforming into the re-animated corpses of his victims, which then proceed to pin him to his bed, disembowel him, and decapitate him. The next morning, detectives break into Frank's apartment and find Frank dead on his bed of a self-inflicted machete wound. After the detectives leave the room to secure the rest of the apartment, however, Frank's corpse opens its eyes.
Frank's motive, and why exactly he does these things -his "fantasies"- is explained when it is revealed that he was abused by his mother.
The film also has a somewhat notorious ending among horror film fans, as it is not only completely open-ended, but provides a variety of possibilities as to what actually occurred, all of them contradictory.
Despite the attention paid to the climax, however, the film's most infamous and widely talked about scene is the "Disco Boy Scene," in which special effects man Tom Savini, dressed in full 1970s disco regalia, has his head blasted off with a shotgun while making out with a woman in the front seat of a vintage car. The scene -filmed in slow motion and lit entirely by the reflected headlights of the car- is extremely graphic and realistic in its depiction of the damage caused by the man's head being blown apart at near point blank range by 12-gauge buckshot; Savini himself was a Vietnam War veteran, and used his firsthand knowledge of the carnage he saw on the battlefield to create the effect.
- Joe Spinell – Frank Zito
- Caroline Munro – Anna D'Antoni
- Gail Lawrence – Rita
- Kelly Piper – Nurse
- Rita Montone – Hooker
- Tom Savini – Disco boy
- Hyla Marrow – Disco girl
- James Brewster – Beach boy
- Linda Lee Walter – Beach girl
- Tracie Evans – Street hooker
- Sharon Mitchell – Nurse #2
- Carol Henry – Deadbeat
- Nelia Bacmeister – Carmen Zito
- Louis Jawitz – Art director
- Denise Spagnuolo – Denise
- Billy Spagnuolo – Billy
- Frank Pesce – TV reporter
- Frank Zito was named after director William Lustig's friend, filmmaker Joseph Zito.
- During the sequence where the nurse, played by Kelly Piper, is stalked in a part of New York City's subway system, some of the graffiti in the scummy bathroom reads "Apocalypse Now!!" a reference to the 1979 film that had come out the year before Maniac's release.
- Many scenes had to be filmed guerrilla-style because the production could not afford permits. The infamous shotgun sequence was one of them; it was filmed in just an hour.
- The character of Frank Zito—including the reasons for his serial murder spree, the fixation on a deceased mother figure, his obvious penchant for sexual perversity and use of his victim's body parts—recalls real-life murderer Ed Gein.
- The song Maniac was written by Michael Sembello and Dennis Matkosky, after Matkosky had been inspired by the film. Its lyrics about a killer were rewritten so that it could be used in the 1983 film Flashdance. The song's use in Flashdance earned it an Academy Award nomination, but it was disqualified when it emerged that the song had not been written specifically for the film.
- Director William Lustig has a small comic cameo as the manager of the "hooker hotel".
- The movie is unrated because it was not submitted to the MPAA; if it had been, it almost certainly would have been given an X rating. The poster does say that "No One Under 17 Will Be Admitted", a practice theatres used for ultraviolent unrated films such as Dawn of the Dead.
- Film critic Gene Siskel vociferously described how sickened he was by the film on Sneak Previews, and walked out thirty minutes into the movie (after the shotgun murder scene), saying the film "could not redeem itself" after the amount of violence shown up to that point. However, in the 1990's Siskel was asked if he had ever walked out of a film and did not mention this one, instead saying he left the 1996 film Black Sheep because of his dislike for Chris Farley.
- Spinell planned to make a sequel titled Maniac 2: Mr. Robbie, in which he would have played a host of a children's television series who murders the abusive parents of his fans. A promo film was made in 1986, but Spinell was unable to find financial backers. Portions of the film can been seen on the DVD release.
- San Francisco's hardcore band Light This City, has as merchandise a vintage t-shirt depicting the movie's poster and the word "MANIAC" replaced by "LIGHT THIS CITY"