The movie He Knows You're Alone was released in 1980 and was directed by Armand Mastroianni. It starred Tom Hanks, in his first major role, as the ex-boyfriend of the reluctant bride, played by Caitlin O'Heaney. The plot revolves around a killer, known as the "Bridal Killer," who targets women who are about to get married and murders them, along with their friends and family.
As the body count rises, a renegade cop named Len Gamble, played by Don Scardino, takes on the case. Len's own fiancée was killed by the Bridal Killer, and he is determined to catch him before he strikes again. Meanwhile, the latest target of the killer is Amy, the reluctant bride, who is having second thoughts about getting married.
As the killer starts to stalk her, Amy begins to question her own sanity, wondering if the Bridal Killer is real or just a figment of her imagination. With the help of her ex-boyfriend, Marvin, played by John Dukakis, she tries to uncover the truth and stay alive.
The movie features a number of suspenseful scenes, including a creepy chase through a movie theater, a tense car chase, and a final showdown between the Bridal Killer and the heroes. While it was not a box office success upon its release, He Knows You're Alone has since become a cult classic among horror fans.