Description
A curse affects the Preston family, caused by their betrayal of the Satanic priest Jonathan Corbis (Ernest Borgnine). Corbis has harassed the Preston family for generations to obtain a Satanic book of great power. Corbis captures patriarch Steve Preston (George Sawaya), who is allowed to escape to warn his wife Emma (Ida Lupino) and younger son Mark (William Shatner) about Corbis\' wrath. He tells them to give the book to Corbis, but during a rainstorm he melts into a waxy substance.
Mark takes the book, hoping to meet with Corbis and defeat him. In a ghost town in the desert, Corbis gives Mark a drink of water from an old hand-pumped well. Mark drinks but then spits out the bitter water. He challenges Corbis to a battle of faith, then draws a pistol and aims it at him. Corbis belittles this threat and Mark tries to escape, but he is surrounded by Corbis\' followers. He produces a cross, but Corbis transforms it into a snake and Mark discards it. Corbis\' followers capture Preston, and Corbis uses a ritual to erase Mark’s memory in preparation for a ceremony later that evening.
Mark\'s older brother, Tom (Tom Skerritt), and his wife, Julie, search for Mark. They are accompanied by Dr. Sam Richards (Eddie Albert), a psychic researcher. Their search leads them to Corbis\' church, where Corbis is performing a ceremony to convert Mark into one of his soulless minions; during the proceedings Corbis transforms into a Satanic demon with large, goat-like horns. Tom witnesses all of this; he is discovered by the Satanists but eludes capture. Later he and Richards meet at the Satanic church, where they discover that the source of Corbis\' power is an ornate glass bottle known as \"The Devil\'s Rain\", which contains the souls of Corbis\' disciples.
Corbis and the Satanists converge on the church. Richards threatens to destroy The Devil\'s Rain, but he is overpowered by the acolytes. He appeals to Mark\'s lost humanity and convinces him to destroy the bottle, which he does in defiance of Corbis\' entreaties. A storm rages outside, and the Satanists melt in the rain. Tom and his wife make a hasty exit. As Tom holds his wife, it is revealed that he is actually embracing Corbis, and his wife\'s soul has become trapped within a new Devil\'s Rain.
