The second Sergeant Cribb Investigation set in the seedy underbelly of Victorian London Pugilism, a brutal form of bare-knuckle boxing, is forbidden by law in late Victorian England, but Sergeant Cribb discovers evidence that it continues in secret, finding a corpse whose hands were “pickled” for fighting. He sends young constable Henry Jago to infiltrate the fighting ring, but Jago is endangered when more murders ensue.