Mateo Melgarejo is a notary public and scribe for the illiterate people of Santo Domingo, a neighborhood north of Mexico City's Zócalo. A squatter friend asks for his help in negotiating with the land census bureau to regularize a land title. After a great deal of frustration with the government bureaucracy, he writes a letter to the cabinet minister, earning an audience with him. The minister hires Melgarejo to reform the bureau, and the appointee proceeds to lecture the officials on their duties in a democratic society. At the end, he gives up the post, returning to Santo Domingo to help its poor residents.
| Writing | Cantinflas | Story |
| Directing | Miguel M. Delgado | Director |
| Writing | Tito Davison | Screenplay |
| Crew | Carlos León | Additional Dialogue |
| Production | Jacques Gelman | Producer |
| Sound | Gustavo César Carrión | Original Music Composer |
| Camera | Jorge Stahl Jr. | Director of Photography |
| Editing | Gloria Schoemann | Editor |
| Art | Salvador Lozano Mena | Production Design |
| Costume & Make-Up | Ana Guerrero | Makeup Artist |
| Costume & Make-Up | Agripina Lozada | Hairstylist |
| Production | Armando Solís | Unit Production Manager |
| Directing | Américo Fernández | Assistant Director |
| Sound | Francisco Alcayde | Sound Recordist |
| Sound | Gonzalo Gavira | Sound Effects |
| Sound | Ramón Moreno | Sound Re-Recording Mixer |
| Sound | Raúl Portillo | Sound Editor |
| Costume & Make-Up | Alfonso Govea | Costume Design |
| Editing | Rosa Schoemann | Assistant Editor |
| Directing | Miguel Ángel Madrigal | Script Supervisor |
