In his first adult role, Mickey Rooney switches from singing and dancing to bobbing and weaving as Tommy McCoy, a hoofer-turned-prizefighter. Lightweight champion Johnny Martin (Mickey Knox), who headlines the show Tommy performs in with his alcoholic father (James Dunn), suggests that
the kid give his fancy footwork a try in the ring, and in no time Tommy faces Martin for the championship, a brutal battle that results in the champ's death and confirms Tommy's all-too-appropriate nickname, "Killer." Distraught, Tommy falls under the influence of Jim Caighn (Brian Donlevy), a
reprehensible gambler, but his daughter (Ann Blyth) falls for the confused fighter and resc...