The mysterious murder of Elspeth Simmons, the adopted daughter of a respectable hat shop owner, was a sensation in London newspapers in 1934. Next to the girl’s corpse, the criminal left two dolls in fancy outfits in the train compartment... But the most important thing: the killer carefully imitated a scene from a new play by the most famous detective writer of the thirties, Josephine Tay, and she herself was the last person to see Elspeth alive! Experienced Inspector Scotland- Yard Archie Penrose is at a loss: what is the meaning of the criminal’s “message”? Perhaps Thay's creations inspired him? Or vice versa? Penrose does not have time to answer these questions: the killer strikes again. This time the victim is the owner of several theaters, where the same play is being sold out... Who's next on the killer's list?