Opera star Gino D'Acosta (Leo Carrillo), due to perform in the open air of the Hollywood Bowl, is warned by a Swami (Pedro de Cordoba)that he will die if he sings. That warning comes to pass and his death proves to be murder. Police detective Steve Farrell (Chester Morris) works backstage to sort out the clues pointing to the identity of the killer. Suspects include a primma donna, her conductor husband, an insane composer, an ambitious singer and a dancer and her husband partner.