A rigid man of fifty leads a solitary, apparently respectable life, as clerk and bookkeeper for a small business and part-time rent collector for his landlord. He has rented a flat in a London suburb for twenty years because deep in its cellar, unbeknownst to anyone else, is a mannequin that he periodically "strangles" in order to satisfy his homicidal urges. The figure's location in the cellar, the darkness, the furtiveness, all are essential for his satisfaction. But his hardly-won balance is threatened when a young man, healthy in mind and body, a doctoral candidate in psychology, becomes a roomer in the house. The danger the older man senses from the moment the new tenant appears is horribly realized for him when the young man finds the mannequin and uses it as the figure in the bonfire at the Guy Fawkes Night celebration he has organized for the local children. The respectable fifty-year-old now must go back to the streets to find flesh more yielding than a mannequin's...