Cantinflas' character Mateo Melgarejo tells the minister that his collection of stamps was a gift from his father who was a mail carrier. Cantinflas' father, Pedro Moreno, was indeed a mail man in Mexico City.
This film was the last appearance of Cantinflas with Spanish actor Ángel Garasa who passed away shortly after this film's release. Garasa began a fruitful career with Cantinflas with the film A volar jóven (1947), playing similar characters. Despite the fact that both actors were of the same generation, Garasa's elderly appearance (in very sharp contrast with Cantinflas' youthful looks) made it easy to give Garasa the role of a mentor or boss to Cantinflas.