The story begins with the narrator, who receives a frantic call from his neighbor, Joan Grissom, claiming a monstrous entity has killed her friends and is attacking her. The narrator, rushing to her aid, discovers a gruesome scene: Joan's friends are brutally murdered. Unfortunately, Joan is kidnapped by the creature before he arrives.

The narrator then encounters Celia La Tour and her brother Bartholomew, who are tracking their enemy, Rackston Bane — the same man terrorizing Joan and her husband, Dick Grissom. Together, they attempt to rescue the Grissoms from Bane's clutches. Bane, driven by vengeance and a warped sense of identity, believes himself to be a Chinese mandarin and employs various monstrous minions, including a hairy beast named Esau, to torture and eventually kill his captives as part of an elaborate, sadistic revenge plan.

The rescue mission leads them to Bane's hideout, where Dick is being tortured in front of Joan, who is bound and slated for a gruesome death. The climax is a chaotic battle that sees the narrator, with the help of Celia and Bartholomew, taking down Bane's henchmen and eventually Bane himself. Celia, despite being fatally wounded, fulfills her promise of revenge by causing Bane's death through a pit of venomous snakes.