Orrie Cather, one of Wolfe's operatives, has been secretly seeing a wealthy man's kept mistress at her secret love nest. He is arrested when she turns up dead. Orrie is the only one of Wolfe's operatives to have the plot of two Stout books turn on his actions: Death of a Doxy and Stout's final work, A Family Affair.
This is one of three Wolfe stories using clueing related to relatively arcane mathematical trivia: "The Zero Clue" in Three Men Out, And Be a Villain, and Death of a Doxy.
"My sister was a what?"
"D ,O, X, Y. Doxy. I happen to like that better than concubine or paramour or mistress. I don't —"
I stopped because I had to, to protect my face.
— Archie Goodwin, conversing with Stella Fleming in Death of a Doxy, Chapter 5
"Fritz came in with a piece of paper in his hand and demanded, 'Were you drunk when you wrote this?'" (p. 117).
Another of my favorite Wolfe novels. As well as being an engrossing story, Death of a Doxy contains IMHO the most sympathetic and positive female character in the Wolfean library: Amy Jackson, a.k.a., Julie Jaquette. Opens with Archie in the apartment of Orrie Cather's murdered lover, Isabel Kerr.