"Who Done It?" - 1942

Two soda jerks dream of writing radio mysteries. When they try to pitch an idea at a radio station, they end up in the middle of a real murder after the station owner is killed during a broadcast.

Who Done It? is a 1942 American comedy-mystery film directed by Erle C. Kenton and starring Bud Abbott and Lou Costello. It is their first feature that contains no musical numbers.