Introduced in 1930 in the novel The Maltese Falcon by Dashiell Hammett, Sam Spade, described as looking like a blond Satan, was notable for his cold detachment, keen eye for detail, and determination to achieve justice on his own terms.  

He was also seen, while still holding on to a “tarnished idealism” as being more than a bit corrupt himself. He soon also appeared in three films, the third and most famous one starring Humphrey Bogart.  

Hammett however never used the character again, saying when asked why that Spade had been shot and killed the next day by Archer’s jealous and jilted wife. 

Pop Culture however was not done with Sam Spade, appearing first in a radio series, he made it into the comics in the 1940s, first in a comic book adaptation of the Maltese Falcon, and then in dozens of comics in the form of full page ads for Wildroot Cream Oil for Hair.  

These appearances took the form of what appeared at first to be regular stories in the comic, only they lasted for only one page, and somehow Wildroot hair tonic always seemed to have something to do with solving the crime in question for at least half the panels.  

Later Sam appeared in the Case Closed manga series and Batman: Detective no 27 as one of the detectives urging Bruce Wayne to become a crime fighter.