Prom Night IV: Deliver Us from Evil

In 1957, Father Jonas killed two teenagers who were having sex in a car. The church authorities then decided not to make this incident widely public, so as not to cast a shadow on the religious institution. They put the young priest in the basement of the church, where he was imprisoned until 1991. And now Father Jonas manages to get out of the basement. A mad priest sets out to exterminate "sinners"...