Swing, Brother, Swing (A Wreath for Rivera) (1949)

Lord Pastern invited his society friends to a swank London nightclub to watch him stage one of his bizarre jokes. But when the joke turned into the "accidental" death of a band member, the laughter stopped. For the audience, it was an open-and-shut case. Everyone had seen the eccentric lord fire the gun. For Inspector Alleyn of Scotland Yard, this case was more bizarre than his lordship's joke--for it wasn't a bullet that killed the accordion player!