Vincent Cartier
Self, Walter's twin brother and manager
Acting
Walter Cartier
Self
Acting
Nat Fleischer
Self, boxing historian
Acting
Bobby James
Self, Walter's opponent
Acting
Judy Singer
Self, female fan in crowd (uncredited)
Acting
Stanley Kubrick
Self (man at ringside with camera) (uncredited)
Directing
Alexander Singer
Self
Directing
Douglas Edwards
Narrator
Acting