One of the most often repeated lines didn’t come from a political speech, a movie, or even a rock song, but from an old time radio show. "Who knows what evil lurks in the hearts of men? The Shadow knows!" was from a show that started in the 1930s.

The line was originally voiced by the narrator of a radio show called "Detective Story". But the eerie character became so popular the show was the renamed "The Shadow".

It was narrated by Frank Readick, Jr., and was accompanied by the musical theme, Camille Saint-Saëns' Le Rouet d'Omphale ("Omphale's Spinning Wheel", composed in 1872). A sinister laugh was also heard from the ominous voice.

The sinister narrator was created to add interest in The Detective Hour radio show and boost sales of the Detective Story Magazine. However, people found the eerie character so compelling that they started asking for the "The Shadow" magazine, even though it didn’t exist.

The Shadow was a vigilante who fought crime using his psychic powers. On the radio show he had the power to seem invisible by influencing the minds of his enemies. Some his more popular nemeses were Kings of Crime and The Red Menace.

The mysteriously cloaked figure with the sinister voice was always clad in black and worked mostly at night. He had the power to defy gravity, unravel codes, speak any language, and had super-human strength.

Some of the most popular of The Shadow radio shows where the ones voiced by Orson Welles.

The character of The Shadow was so well loved that he was eventually featured in motion pictures, comic books, television shows, and even video games. The magician Walter B. Gibson wrote much of the material that turned The Shadow into a pulp icon. He wrote under the pen name Maxwell Grant and other writers eventually wrote the stories under the name, also.

At the end of each show The Shadow reminded listeners, "The weed of crime bears bitter fruit. Crime does not pay.... The Shadow knows!"

Though the lines of The Shadow have remained famous, at one time it was heard to track down episodes of the radio show. But that is no longer true. Thanks to the internet you can now find copies of this and many other radio shows.

The Shadow ran until 1954 and is still a favorite old time radio show.