This film was released in Mexico in 1961; most sources credit it as having been produced in 1958, but a newspaper in the film appears to bear a July 1959 date.
Cerebro del Mal is a very unusual Santo film in many ways: in the first place, Santo is never called "Santo" in the picture at all! He is ONLY referred to as "El Enmascarado," while the other masked wrestler (Fernando Osés--who has a brief dual role in the final scene) is called "El Incógnito" ONCE. Santo has practically no dialogue (in fact, the dialogue for all of the characters for the whole film would probably only take up about 3 typed pages), is given no "origin," is not depicted as a professional wrestler (there are no arena bouts included), and is relatively incidental to the plot. Santo himself, looking uncharacteristically slim (compared to later films), appears rather awkward and ill-at-ease.