Mammy features Al Jolson as the star of a travelling minstrel show, appearing in a small Southern town. Jolson falls in love with an actress in the troupe (Lois Moran), but she loves another. One of Jolson's fellow minstrels (Lowell Sherman) is shot backstage, and it is assumed thanks to several plot convolutions that Jolson is guilty of the deed.
| Directing | Michael Curtiz | Director |
| Writing | Irving Berlin | Theatre Play |
| Writing | James Gleason | Theatre Play |
| Writing | Gordon Rigby | Writer |
| Camera | Barney McGill | Director of Photography |
| Sound | Louis Silvers | Original Music Composer |
| Editing | Owen Marks | Editor |
| Production | Walter Morosco | Producer |
| Costume & Make-Up | Orry-Kelly | Costume Design |
| Sound | George Groves | Sound |
| Writing | Joseph Jackson | Writer |
