Dr. Sophie Knowles teaches math at Henley College in Massachusetts, but when a colleague turns up dead, it's up to her to find the killer before someone else gets subtracted

It is a sociological story of urban class warfare and political intrigue, taking place in the fictional South American capital city of Vados. It explores the idea of subliminal messages as political tools, and it is notable for having the structure of the famous 1892 chess game between Wilhelm Steinitz and Mikhail Chigorin. The structure is not coincidental, and plays an important part in the story. Nominated for Hugo Award for Best Novel in 1966

Both Nero Wolfe and Archie Goodwin are at their furious best when a murder is committed with Archie’s gun and the client lies to the cops, indicating that Goodwin is the prime suspect. Inspector Cramer threatens to cancel Wolfe’s detective license and arrests Archie. Wolfe is so angry that he works during an orchid session, begins a million dollar suit against the client, and reveals Cramer’s threat to the newspapers before finally exposing the culprit; Archie merely slams the client against a wall