Another Carolus Deene novel, this mystery in particular is considered one of Bruce's cleverest and best plotted.
Leo Bruce was the pen name of Rupert Croft-Cooke, who wrote more than twenty highly-praised mysteries featuring Carlous Deene. He also wrote eight mysteries featuring Sgt. William Beef, a cockney police detective who invariably "knows who done it." Croft-Cooke died in 1980.