When we think of a Hard-Boiled Detective, the image that first pops into our heads is none other than Sam Spade.
The question is: how accurate is that picture? The answer is both "very" and "not very". It is far from uncommon for a character or even a story to be modified from the original author's vision. This is especially true when a literary character is adapted for other media. What is interesting in Sam Spade 's transformation is that the more he is adapted, the more correct he feels to the audience.
Convention dictates that the Sam Spade introduced to us by Dashiell Hammett would be the correct one. Spade seems to be an amalgam of the actual private detectives that Hammett had worked with when he was an investigator. In the introduction, to the 1934 edition of The Maltese Falcon, Hammett writes that the real private detective has no desire "to be an erudite solver of riddles in the Sherlock Holmes manner; he wants to be a hard and shifty fellow, able to take care of himself in any situation, able to get the best of anybody he comes in contact with..." Spade is introduced to the world in The Maltese Falcon, which was serialized in the pages of Black Mask magazine, beginning with the Sept 1929 issue. The serial was published as a novel the next year. The Spade introduced in The Maltese Falcon is not a likable hero; called a blonde Satan, he has little respect for anyone, including his partner, with whose wife he occasionally sleeps. He is a man who has "seen the wretched, the corrupt, the tawdry side of life but still maintains his 'tarnished idealism'".
Sam Spade first came to the screen in Warner Bros. 1931 production. Star Ricardo Cortez was a good physical match for Hammett's character, and the cast was filled with actresses who were "easy to look at". The film was a success, but when Warner tried to re-release the picture in 1936 it was blocked by the Production Code Office for "lewd content". Unwilling to let a hot property rot, the studio re-shot the picture with different actors and character names under the title Satan Met A Lady. The new picture was a flop that couldn't decide "whether to be a screwball comedy or a murder mystery".
First time director John Huston landed the assignment to film the third version of the story. The resulting 1941 film became one of the greatest movies of all time. Huston managed this in part by remaining (mostly) faithful to the original novel (allegedly, Huston tossed a copy of the book top his secretary and told her to type up the dialog), but he made a departure by casting Humphrey Bogart in the lead. Bogie was criticized as being too short and too dark to play Sam Spade. However, Sam Spade's character traits would be forever associated with Bogart, and vice-versa. The film noir tradition of the Hard-Boiled Detective became incredibly popular in the post-war era, and every leading man who wore a snarl and a fedora was doing an imitation of Bogie.
Bogie was not the first to bring Sam Spade to the radio. The Lux Radio Theater production in Feb 1943 starred Edward G. Robinson, but Bogart assumed the role for the Screen Guild Theater in Sept of that year, and again in the Jul 1946 version for The Academy Award Theater.
Sam Spade was too good of a character for Radio to ignore. Suspense! producer/director William Spier took the helm of The Adventures of Sam Spade for CBS in 1946, starring Howard Duff as the detective, and Lurene Tuttle as his devoted secretary, Effie. Duff's Spade is a generally more likable and personable character. He relates his cases on the radio by dictating the reports to Effie.
The only true sequel to The Maltese Falcon was "The Khandi Tooth Caper" which brought the surviving characters of the original story to the radio for a two part episode of the Adventures of Sam Spade . When Suspense! adopted a sixty-minute format during the first half of 1948, Spier bought his Sam Spade cast and the story to the Anthology as a single episode.