Based on the true story of Richard Trenton Chase, "The Vampire Killer" who killed six people in the course of four days in January 1978.
The film was set for release in late 1987, but went unreleased in America for five years when its distributor, De Laurentiis Entertainment Group, went bankrupt. William Friedkin reedited the film and changed the ending before Miramax Films eventually picked it up and gave it a limited run in 1992.
In filming the scene where Alex McArthur's character jumps through the church window, McArthur insisted on doing his own stunt. Unfortunately, when he landed on the floor he fractured his ankle. He was taken to a local hospital where a cast was put on the lower portion of his leg. Later in the same scene, when he is knocking over items on a table, a black stocking can clearly be seen covering the cast.
Due to legal complications, this film wasn't shown theatrically in America until several years after its European debut. It was released on laserdisc in Japan sometime in 1990, and these copies were imported to the United States.