 | Dean Martin als Dr. Steven Harris |
 | Jerry Lewis als Homer Flagg |
 | Janet Leigh als Wally Cook |
 | Edward Arnold als The Mayor of New York |
 | Fred Clark als Oliver Stone |
 | Sheree North als Jitterbug Champion |
 | Sammy White als Waiter |
 | Sid Tomack als Master of Ceremonies |
 | Sig Ruman als Dr. Emile Egelhofer |
 | Richard Loo als Dr. Lee |
 | Raymond Greenleaf als Conductor |
 | Walter Baldwin als Isaiah Jackson |
 | Fay Roope als Man |
 | Fritz Feld als Barber (uncredited) |
 | Dabbs Greer als Scouts Leader (uncredited) |
 | Grady Sutton als Gift Shop Clerk (uncredited) |
 | Kathryn Grant als Manicurist (uncredited) |
 | Bess Flowers als Patron at Wonderland Ballroom (uncredited) |
 | Eduard Franz als Dr. Nassau (uncredited) |
 | Marla English als Manicurist |
 | Charles Fogel als City Official (uncredited) |
| Norman Taurog | Director |
| Clem Jones | Second Assistant Director |
| Jack Rose | Screenplay |
| Melville Shavelson | Screenplay |
| Ben Hecht | Theatre Play |
| James H. Street | Story |
| Daniel L. Fapp | Director of Photography |
| Hal Pereira | Art Direction |
| Albert Nozaki | Art Direction |
| John P. Fulton | Special Effects |
| Sam Comer | Set Decoration |
| Emile Kuri | Set Decoration |
| Michael D. Moore | Assistant Director |
| Archie Marshek | Editor |
| Edith Head | Costume Design |
| Arthur Rosson | Second Unit Director |
| W. Wallace Kelley | Second Unit Director of Photography |
| Gene Merritt | Sound Recordist |
| Gene Garvin | Sound Recordist |
| Rudy Makoul | Dialogue Coach |
| Jack Mintz | Producer's Assistant |
| Paul Jones | Producer |
| Nick Castle | Choreographer |
| Walter Scharf | Music Arranger |
| Walter Scharf | Conductor |
| Jule Styne | Music |
| Bob Hilliard | Lyricist |
| Jule Styne | Songs |
