Fast-talking manager Nettie (Ida James) helps legendary jazz bandleader Cab Calloway (Cab Calloway) land a steady gig at the exclusive Brass Hat Club. Upon hearing the good news, Calloway's untrusting girlfriend, Minnie (Jeni Le Gon), mistakenly assumes that he and Nettie are having an affair. As Calloway and his band prepare for their maiden performance at the Brass Hat, the vengeful Minnie asks Boss Mason (George Wiltshire) -- the thuggish owner of a competing club -- to put a hit on her man.