Various murders are examined by a private investigator.
| Actor | Role |
|---|---|
 Adalberto MartínezAmado | Amado |
 Óscar PulidoOscar | Oscar |
 María Eugenia San MartínRosita | Rosita |
 Pedro de AguillónArístides Galván | Arístides Galván |
 Luis AragónDon Lauro | Don Lauro |
 David SilvaDoctor Ingemar | Doctor Ingemar |