Sam Spade aired on CBS Radio July 4, 1948 - B093 The Rushlight Diamond Caper stars Howard Duff as Spade. The Adventures of Sam Spade was first heard on ABC July 12, 1946, as a Friday-night summer series. The show clicked at once, and went into a regular fall lineup on CBS September 29, 1946. From then until 1949, Sam Spade was a Sunday-night thriller for Wildroot Cream Oil. When a simple job of guarding wedding presents turns deadly, Sam is thrust into the tasteless world of the elite.  He must wade through an arranged marriage, greedy guardians, and calloused companions to reach the bottom of the Rushlight diamond mystery. Sam Spade is perhaps the most famous of all hard-boiled detectives, creator Dashiell Hammett only featured the character in a single novel, The Maltese Falcon, and three short stories. Hammett wrote from experience, having served eight years as a detective with the Pinkerton Agency. His cases had included investigations of Fanny Brice's gangster husband Nicky Arnstein and the infamous Fatty Arbuckle scandal. Hammett based many of his stories on actual people and cases, but insisted that Sam Spade had no real-life counterpart, and was instead an "idealized" version of "what most of the private detectives I've worked with would like to have been."