Patriarch Steve Preston goes missing and worried mom Emma (Ida Lupino) sends eldest son Mark (William Shatner) in search for his father. Suddenly, a dying, eyeless Steve returns and demands that the family: "Give Corbis what belongs to him!" before dissolving into a gelatinous meltdown. Corbis (Ernest Borgnine) is a Satanic priest hell-bent on recovering a valuable book listing the names of those who sold their souls to the devil... a book that resides with the Preston family. Occult expert, Dr. Richards (Eddie Albert) and Mark's younger brother, Tom plot to free the Prestons and destroy the Devil's Rain, a bottle containing the souls of those already damned.