Fact1: Billy takes so long, Fact2: decision was influenced by fate of wife and son, Fact3: wife and son were converted to new faith by local nobleman, Fact4: first couple 's friends set out on private mission to find Daphne, Fact5: Lawrence decides to offer her in attic
Output: In 1920s England, a group of upperclass people take part in an automobile race to Lands End. One couple, Billy and Daphne, get lost in heavy fog and run out of petrol. Billy goes to look for fuel, but takes so long that Daphne strikes out on her own. She eventually locates a rural estate owned by Dr. Lawrence, a former priest. He receives her kindly and sends his disturbed gardener, Tom, to find Billy. Tom finds and murders Billy, and pushes the car into a ravine; it is implied that he acted on his employers orders. Meanwhile, Dr. Lawrence tells Daphne about a trip his family took to India; his experiences with certain cults there so horrified him that he renounced religion in general. This decision was heavily influenced by the fate of his wife and son, who were converted to a new faith by a local nobleman. The former was afterwards so horrified by the things she had done that she committed suicide. Still waiting for Billy, Daphne falls asleep in a guest room. Seeing this, the doctors Indian housekeeper, Ayah, goes to the houses attic and lets out a bloated, bloodstained man in a priests mantle. He kills Daphne with a katar, and Ayah ritually cooks the girls flesh for him to eat and burns the girls clothes. The first couples friends, Geoffrey and Angela, learn of Billys death from the police and set out on a private mission to find Daphne. They too wreck their car in the fog and are separated in the search for help. The local police refuse to search the marshland as it is too dangerous. Angela locates the Lawrence estate first, and is abducted by Tom, who obviously hopes to rape her. When Dr. Lawrence discovers her presence, he reluctantly decides to offer her as another sacrifice to the ghoul in his attic. She is saved from molestation when Tom is sent out to get rid of Geoffrey, who also found the house and was convinced by Dr. Lawrence that Angela and Daphne were both conveyed safely back to town. Tom botches the attempt to kill Geoffrey, and is half sucked into a bog in his attempt to flee. Ordered to explain himself before he is rescued, he admits that Daphne was fed to something living in Lawrences house. Geoffrey returns to the estate and confronts Lawrence, who admits that the ghoul is his own son; the man has been a cannibal ever since his conversion, and Ayah is another cult adherent who came from India to prepare his food. The agonized Lawrence has tended to and protected his son because he promised his wife he would do so. Geoffrey barges into the attic and confronts the ghoul, who kills him. Meanwhile, Tom sneaks into the room where Angela is imprisoned and again tries to assault her. He is interrupted and killed by the ghoul, who has gotten out of control. The creature rounds on Angela, but Lawrence enters with a pistol and fatally wounds it. Angela runs screaming from the house. Dr. Lawrence, his heart broken by what has happened, goes to his study and shoots himself through the head.