I Was A Teenage Werewolf 1957

I Was a Teenage Werewolf is a 1957 American science fiction horror film directed by Gene Fowler Jr., and starring Michael Landon as a troubled teenager, Yvonne Lime and Whit Bissell. Co-written and produced by cult film producer Herman Cohen, it was one of the most successful films released by American International Pictures.
The film was originally released as a double feature with Invasion of the Saucer Men. The release included the tagline, "We DARE You To See The Most Amazing Motion Pictures Of Our Time!"
Tony Rivers, a troubled teenager at Rockdale High, has a short and explosive temper which gets him into numerous fights. Local police Detective Donovan advises Tony to talk with a psychologist that works at the local aircraft plant, Dr. Alfred Brandon, a practitioner of hypnotherapy. Tony declines, but his girlfriend Arlene, as well as his widowed father Charles, show concern about his violent behavior. At a Halloween party at the "haunted house", an old house at which teenagers hang out, Tony attacks his friend Vic after being surprised from behind. After seeing the shocked expressions on his friends' faces, he realizes he needs help and goes to see Dr. Brandon.
Brandon concludes Tony's troubled history makes him an excellent subject for his experiments with a scopolamine serum he has developed that regresses personalities to their primitive instincts. Brandon believes that the only future that mankind has is to "hurl him back to his primitive state." Although Brandon's assistant, Dr. Hugo Wagner, protests that the experiment might kill Tony, Brandon injects Tony with the serum, telling Tony it is a sedative to prepare him for hypnosis. During a series of hypnosis sessions, Brandon draws out Tony's traumatic childhood memories and suggests to Tony that he was once a wild animal.
After a small party at the haunted house, Tony drives Arlene home. One of their buddies, Frank, is attacked and killed as he is walking home through the woods. Donovan and Police Chief Baker review photographs of the victim and notice the fatal wounds look like fang marks, but there are no wild animals in the area. Pepi, the police station's janitor, persuades officer Chris Stanley to let him see the photos. Pepi, a native of the Carpathian Mountains, where werewolves, "human beings possessed by wolves", are common, recognizes the marks on Frank's body. Chris, however, dismisses the idea of a werewolf.
After another session with Brandon, during which Tony tells the doctor that he feels that there is something very wrong with him, Tony reports to Miss Ferguson, the principal of Rockdale High. Miss Ferguson tells Tony that Brandon has given him a positive report regarding his behavior, and that she intends to recommend Tony for entry into State College. As Tony leaves the school, he passes the gymnasium where a woman, Theresa is practicing by herself. A school bell behind his head rings, triggering his transformation into a werewolf, and he attacks and kills etc..