Sam Spade, the protagonist of Dashiell Hammett’s The Maltese Falcon, first appeared Black Mask magazine before publication in book form in 1930. Despite being an instant success, Hammett never wrote another book about his ultra hardboiled PI, though he did appear again in three short stories published in 1932. Between 1931 and 1941, as discussed with Mark Dillon on the last episode of Fedora, Warner Bros released three films based on the novel, with a different actor playing the main role each time. However, it was on radio that Spade had his most consistent success. The Adventures of Sam Spade, as the half-hour show was called, made its debut on 12 July 1946, starring Howard Duff as Spade and Lurene Tuttle as his secretary, Effie Perrine. The show moved from ABC to CBS and then NBC, running for a total of 245 episodes. On top of that, Duff and Tuttle reprised their roles in a special 1-hour episode of Suspense, in which Sam Spade briefly met Philip Marlowe (as played by host Robert Montgomery). That episode is presented here in its entirety. 

Suspense / The Kandy Tooth Caper (CBS, 10 January 1948) Written by Bob Tallman and Jo Eisinger; Director: William Speir; Cast: Robert Montgomery (series host / Philip Marlowe), Howard Duff (Sam Spade), Lurene Tuttle (Effie Perrine), Joe Kearns (Casper Gutman), Cathy Lewis (Hope Laverne), Wally Maher (Lawrence Laverne), Jay Novello (Joel Cairo), Jeanette Nolan (Mrs. Julius), Jack Edwards, Jr. (Herman Julius / mortuary attendant), Sidney Miller (documentary narrator), Hans Conried (Marvin / Don Constantino), Bill Johnstone (Lieutenant Dundy).