Recommended reading - Unknown Man #89, by Elmore Leonard (1977):

Unknown Man #89

By Elmore Leonard.

Published by Mariner Books.

First published 1977.

Paperback.

ISBN-10: 006218928X

ISBN-13: 978-0062189288

Description:

“The greatest crime writer of our time, perhaps ever!” – The New York Times Book Review.

“An absolute master.” – The Detroit News.

“No one is Leonard’s equal,” declares the Chicago Tribune – and anyone who might doubt it would only have to read Elmore Leonard’s riveting noir classic, Unknown Man #89, to become a true believer.

Detroit process server Jack Ryan has a reputation for being the best in the business at finding people who don't want to be found. Now he's looking for a missing stockholder known only as "Unknown Man No. 89." But his missing man isn't "unknown" to everyone: a pretty blonde hates his guts and a very nasty dude named Royal wants him dead in the worst way. Which is very unfortunate for Jack Ryan, who is suddenly caught in the crossfire of a lethal triple-cross and as much a target as his nameless prey.

The twisty tale of a Detroit process server whose search for a missing stockholder leads him into more serious peril than he ever imagined possible, Unknown Man #89 is a gourmet stew of mystery, suspense, and double and triple cross, peppered with the razor-sharp dialogue for which Grand Master Leonard is justifiably famous.

Exhilarating old-school crime fiction that the late, great John D. MacDonald, Dashiell Hammett, James M. Cain, and Robert Parker would have been proud to call their own, Unknown Man #89 is a gem – nothing less than we’d expect from the man who created the incomparable U.S. Marshal Raylan Givens of the hit TV series Justified.