The Maltese Falcon, by Dashiell Hammett (PB, 1984, reading copy only, $0.50)
I loved the movie.
All the characters are here in the original novel- Sam Spade, Miles Archer, the Fat Man, Brigid O'Shaughnessy, and Joe Cairo. But which do you prefer? The novel or the movie? Or do you like them both?
Look for this book in the PB section, avail 12/7.
(Did you know Hammett also wrote The Thin Man?)