I nominate
Fast One by Paul Cain.
This was Cain's only novel. He is considered by some to be the most hard-boiled of writers.
“In the matter of grim hardness Dashiell [Hammett] paused on the threshold. Paul [Cain] went all the way.” —Captain Joe Shaw, editor of Black Mask during its golden era
“[Fast One represents] some kind of high point in the ultra hard-boiled manner.” —Raymond Chandler, author, The Big Sleep
Amazon - $4.99
https://www.amazon.com/Fast-One-Paul...dp/B00B132H2O/
Nook - 99 cents
http://www.barnesandnoble.com/w/fast...=2940150605152
Kobo - 99 cents
https://store.kobobooks.com/en-us/ebook/fast-one-2