Rita La Roy has good reasons to hate her philandering husband, Hooper Atchley, in this low-budget but sumptuous-looking art deco mystery directed by comedy specialist Thornton Freeland. The cool and calculated Miss La Roy isn't the only person with a grudge against the nasty Atchley, however; in fact, quite a few people come under suspicion when the philanderer is found dying from a bullet wound in his penthouse apartment. Just before he expires, Atchley manages to gasp, "Casey," referring perhaps to Arthur Jones (William Collier Jr.), whose sister (June Clyde) was one of the evil man's latest victims. In the middle of the investigation, the murder scene is plunged into darkness, a shot is fired, and when the electricity returns, yet another victim is found, with the late Mr. Atchley's pet monkey -- the secret witness -- clutching a still smoking gun. Police Captain McGowan (Purnell Pratt) is at first dumbfounded, but with the help of dizzy neighbor Una Merkel, the identity of the murderer is finally revealed.