On the surface, life is going well for Sir Maurice Newbury, who has brilliantly solved several cases with Miss Veronica Hobbes by his side. But he has succumbed to addiction, and Veronica and Bainbridge must drag him from an opium den to investigate a series of copy-cat crimes, the criminal himself already in the morgue. Newbury thinks that the details are too perfect for it to be the work of a copycat. But how can the dead commit a crime?