Agatha Christie 
The Mysterious Affair at Styles (Diversion Classics) [EPUB ebook] 

Featuring an appendix of discussion questions, the Diversion Classics edition is ideal for use in book groups and classrooms.
In Agatha Christie’s first novel, famous Belgian inspector Hercule Poirot investigates the murder of a wealthy old woman, Mrs. Inglethorp. The suspects range from Mrs. Inglethorp’s young husband to her stepson, and Christie’s mastery of suspense keeps the reader guessing until the very end. A hallmark of detective fiction, THE MYSTERIOUS AFFAIR AT STYLES is required reading for mystery lovers.