Local idiot Ichabod Mudd dresses up and plays at being superhero Sargeant Twilight (an imitation of Captain Midnight). He mistakes this violin-case toting actual conductor for Mugs Matson, a train conductor turned holdup artist who carries a tommy gun in a violin case. He tackles him, spraining his conducting wrist, so he can't do the concert that evening.
Sgt. Twilight bee-esses that he'll conduct the unnamed orchestra instead. Which he actually ends up doing, while dodging bullets from Mugs Matson, whom he's challenged.
From Fawcett comic book Captain Midnight #41 (June 1946).