Sing sing nights

In a framing sequence, three prisoners have been sentenced to death for the same murder. One must be innocen, but all three claim responsibility. A pardon is offered to the one who tells the best story. The three tales told comprise the majority of the book. One story is a crime story about the search for the "12 coins of Confucius", one involving a masquerade party and a moth costume, and one is about a human brain transplanted into the body of a gorilla.