Mr. Banjo
One of Captain Marvel's recurring villains from the early issues of Captain Marvel Adventures in the 1940s, first appearing in "Captain Marvel Adventures" #8. Kurt Filpots worked as an agent for the Axis powers during World War II. Dressed as a stout man in a shaggy green suit and straw hat who carried around an old banjo with him, Filpots delivered secrets to the Japanese in the form of musical notes. Someone in a military meeting would whistle musical notes which were a code, Banjo would play the music next to a house with an agent inside who would radio them to the Japanese. Although evil, Mr. Banjo would go up against Captain Marvel with nothing more than a banjo. In his first appearance he was apparently killed when thrown off a ship by Captain Marvel. In his next appearance, he kidnapped the President of the United States and replaced him with an imposter that gave orders for the Navy to leave the Pacific which would allow the Japanese fleet to advance, but was captured this time. He was a member of the Pre-crisis Monster Society of Evil.
He was recently featured on the Robot Chicken DC Universe Special in a segment called "Real Characters From the DC Universe", voiced by Aaron Paul.
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