(Source: Wikipedia)
The original SHADOW radio series was actually conceived as a way to sell comic magazines.
In order to boost the sales of their Detective Story Magazine, Street and Smith Publications hired David Chrisman of the Ruthrauff & Ryan advertising agency and writer-director William Sweets to adapt the magazine's stories into a radio series.
The character, 'The Shadow,' would go on to become a major influence on the subsequent evolution of comic book superheroes, in particular, Batman.
While searching for a narrator played by a mysterious storyteller with a sinister voice, one of the scriptwriters suggested various possibilities such as 'The Inspector' or 'The Sleuth.' He eventually proposed the ideal name for the phantom announcer: "...The Shadow."
Although Street and Smith, the nation's oldest and largest publisher of pulp magazines had hoped the radio broadcasts would boost the declining sales of the Detective Story Magazine, the result was quite different. Listeners found the sinister announcer much more compelling than the unrelated stories. They soon began asking news dealers for copies of "that Shadow detective magazine," even though it did not exist.
In the radio drama, which debuted in 1937, The Shadow was an invisible avenger who had learned, while "traveling through East Asia," "the mysterious power to cloud men's minds, so they could not see him." This feature of the character was born out of necessity: time constrains of 1930s radio made it difficult to explain to listeners where The Shadow was hiding and how he was remaining concealed.
As originally conceived, Lamont Cranston ('The Shadow') is really an alias as well. The Shadow's real name was Kent Allard, a famed aviator who fought for the French during World War I. Allard assumed several aliases including the 'Dark Eagle' After the war, Allard finds a new challenge in waging war on criminals. He fakes his death in the South American jungles, then returns to the U.S. Arriving in New York City, he adopts numerous identities to conceal his existence. . One of these identities -- indeed, the best known -- is that of Lamont Cranston, a "wealthy young man about town."
In the detective magazine, Allard frequently disguises himself as Cranston and adopts his identity. While Cranston travels the world, Allard assumed his identity in New York. In their first meeting, Allard, as The Shadow, threatens Cranston, saying he has arranged to switch signatures on various documents and other means that will allow him to take over the Lamont Cranston identity entirely unless Cranston agrees to allow Allard to impersonate him when he is abroad. Terrified, Cranston agrees. The two men sometimes meet in order to impersonate each other. The disguise works well because Allard and Cranston resemble each other.
In the radio drama, the Allard secret identity was dropped for simplicity's sake. On the radio, The Shadow was only Lamont Cranston; he had no other aliases or disguises.
Though initially wanted by the police, the Shadow also works with and through them, notably gleaning information from his many chats with Commissioners Ralph Weston and Wainwright Barth. Weston believes that Cranston is merely a rich playboy who dabbles in detective work.
In contrast to the pulps, The Shadow radio drama limited the cast of major characters to the Shadow, Commissioner Weston, and Margo Lane, the last of whom was created specifically for the radio series, as it was believed the abundance of agents would make it difficult to distinguish between characters.
The Shadow faced a wide variety of enemies, ranging from kingpins and mad scientists to international spies and "super-villains," many of whom were predecessors to the rogues galleries of comic super-heroes.
Following a brief tenure as narrator of Street & Smith's Detective Story Hour, "The Shadow" character was used to host segments of The Blue Coal Radio Revue, playing on Sundays at 5:30 p.m. Eastern Standard Time. This marked the beginning of a long association between the radio persona and sponsor Blue Coal.
While functioning as a narrator of The Blue Coal Radio Revue, the character was recycled by Street & Smith in October 1931, to oddly serve as the storyteller of Love Story Hour.
The Shadow returned to network airwaves in September 1937 over the new Mutual Broadcasting System. Thus began the "official" radio drama, with 22-year-old Orson Welles starring as Lamont Cranston. The half-hour series would continue until December 26, 1954. Welles did NOT speak the signature line, "Who knows what evil lurks in the hearts of men?" Instead, it was again spoken by Frank Readick, who was originally tapped in the early 30s to play the role. Readick used a water glass next to his mouth to create the echo effect. The famous catch phrase was accompanied by the strains of an excerpt from Opus 31 of the Camille Saint-Saens classical composition, Le Rouet d'Omphale. Welles departed the show in 1938.
The radio drama also introduced female character in The Shadow's realm, most notably Margo Lane (played by Agnes Moorehead, among others) as Cranston's love interest, crime-solving partner and the only person who knows his identity as The Shadow. Four years later, the character was introduced into the pulp novels. her sudden, unexplained appearance in the pulps annoyed readers and generated a flurry of hate mail printed in The Shadow Magazine's letters page. Lane was described as Cranston's "friend and companion" in later episodes, although the exact nature of their relationship was unclear. In the early scripts of the radio drama the character's name was spelled "Margot." The name itself was originally inspired by Margot Stevenson, the Broadway ingenue who would later be chosen to voice Lane opposite Welles' Shadow during "the 1938 Goodrich summer season of the radio drama." In the 1994 film in which Penelope Ann Miller portrayed the character, she is characterized as a telepath.
due to pulp paper shortages during WWII and the growing amount of space required for war news from both the European and Pacific fronts, The Shadow comic strip was canceled on June 13, 1942 after two years and nine adventures had been published.