Mateo Melgarejo (played by Mario Moreno "Cantinflas") 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.
The comedian La India María had replaced the "Cantinflas" character as the cinematic icon of Mexico's urban and rural poor, and critics viewed El ministro y yo as an attempt by Moreno, whose media influence made him one of Mexico's elite, to get back into touch with the common people. The unrealistic portrayal of a sympathetic cabinet minister and the unlikely appointment of a "commoner" to a position of power did not reverberate with the public.