Mexican horror movies of the 60s featured a lot of vampires and mummies (and wrestlers), but not very many werewolves; in fact, this is the only Mexican lycanthrope movie that I can recall. We do, however, get more than one hairy horror for our money...
Joaquín Cordero plays Dr. Alejandro Bernstein, who visits Profesor Fernandez (José Elías Moreno) to ask for the hand in marriage of his daughter Clarisa (Kitty de Hoyos); Bernstein's arrival coincides with several brutal slayings by a creature who prowls whenever there is a full moon.
The werewolves in this film are particularly savage: snarling ravenous beasts that stalks their prey before leaping into action (with the help of a carefully hidden springboard) and ripping them to pieces and tearing out the victim's heart (which means we are treated to some brief black and white gore). The film is also unusual in the fact that a werewolf can only be killed-not by a silver bullet-but by a dagger with an ivory blade or by a specially trained dog!
The vicious monster(s) and the film's more unique elements help compensate somewhat for an otherwise rather pedestrian plot. And we should always be grateful, I suppose, that there isn't any wrestling!