Lady Betty Calder

Lady Betty Calder is a prostitute and a blackmailer - or is it her sister, Glynis, using her name? Dr David Garth, her fiancé, knows he must find out the truth - especially when he blunders across Glynis'' strangled body on Betty''s property.

The police know she did it, but David knows she didn''t, and he must outwit a cunning murderer and a hostile detective-inspector to prove it. What he discovers - about his best friend''s wife, his medical assistant, and even his fiancée - make him wish the blackmailing Glynis had never lived.

''John Dickson Carr''s flair for the impossible crime shows through at its very best in this historical puzzler'' The Times