A mentally unbalanced man is obsessed with the idea that a black cat is possessed. He tortures and kills it. Later, he comes to believe that the cat has returned from the dead to kill him.
Thomas P. Manning, businessman and chess expert mysteriously shot in a locked room, dies clutching some chess pieces. Police are baffled, and finally abandon the case. Six months later, victim's daughter Leah Manning, stung by a scurrilous book about the case, enlists the aid of Charlie Chan and Number 3 Son. Additional murders follow, leading to a climactic confrontation in a seemingly deserted "Fun House."