Cesar Martin, better known as El Duque, is an elegant, charming and intelligent man, who has been obliged to be known by heart the Penal Code, as their profession is the scam. Cesar has another weakness: his beautiful daughter Silvia is always a decent person.
| Directing | Germán Lorente | Director |
| Writing | Ángel G. Gauna | Writer |
| Writing | Germán Lorente | Screenplay |
| Writing | Germán Lorente | Story |
| Writing | Rafael J. Salvia | Screenplay |
| Writing | Rafael J. Salvia | Story |
| Production | José Truchado | Executive Producer |
| Sound | Gregorio García Segura | Music |
| Crew | Raúl Artigot | Cinematography |
| Editing | José Luis Matesanz | Editor |
| Art | Pablo Gago | Set Decoration |
| Costume & Make-Up | Paloma Pardo | Hairstylist |
| Costume & Make-Up | Dolores Merlo | Makeup Department Head |
| Costume & Make-Up | Josefa Morales | Assistant Makeup Artist |
| Production | Ángel Quintana | Production Manager |
| Directing | Ángel G. Gauna | Assistant Director |
| Art | Manuel Rincón | Property Master |
| Camera | Ramón Sempere | Camera Operator |
| Camera | José Salvador | Still Photographer |
| Camera | Santiago G. Merodio | Assistant Camera |
| Camera | Luis Caldery | Assistant Camera |
| Crew | Toledano Hermanos | Generator Operator |
| Editing | María Luisa Ocaña | Assistant Editor |
| Production | Eugenio Villar | Production Assistant |
| Directing | María Luz Manzano | Script Supervisor |