Mercedes works as a cabaret performer to pay for her sister's studies. Problems begin when Mercedes and Paco, her exploiter, win a dance contest, but he refuses to share the prize with her.
| Directing | Emilio Fernández | Director |
| Writing | Emilio Fernández | Writer |
| Writing | Mauricio Magdaleno | Story |
| Production | Salvador Elizondo | Producer |
| Production | Fernando Marcos | Executive Producer |
| Sound | Antonio Díaz Conde | Music |
| Camera | Gabriel Figueroa | Director of Photography |
| Editing | Gloria Schoemann | Editor |
| Art | Jesús Bracho | Production Design |
| Production | Alberto A. Ferrer | Production Manager |
| Directing | Felipe Palomino | Assistant Director |
| Costume & Make-Up | Ana Guerrero | Makeup Artist |
| Costume & Make-Up | María E. Salazar | Hairstylist |
| Sound | José de Pérez | Sound Re-Recording Mixer |
| Sound | Rodolfo Solís | Sound Recordist |
| Lighting | Daniel López | Lighting Technician |
| Camera | Ignacio Romero | Camera Operator |
| Camera | Pablo Ríos | First Assistant Camera |
| Directing | Manuel Alcayde | Script Supervisor |
