Producer Alberto Lopez cut ties with lucha libre star Santo after Santo contra el espectro del estrangulador (1965) was finished, but the producer decided to cash-in on the success of his previous films by making a Santo rip-off named El enmascarado de Oro (Man in the Golden Mask) played by Jorge Rivero, who would go on to co-star in two Santo films: Operación 67 and El tesoro de Moctezuma.
It is unknown wether this film was supposed to be a Santo movie or an original production but it doesnt seem like a far fetched idea. Its mostly an average entry in the genre with the usual filler and dancing numbers that take a good amount of screentime in these Alberto Lopez productions. The Man in the Golden Mask could easily be replaced with Santo and the generic villain and storyline are also very derivative but its decently executed and with satisfying effects for the time and budget.
Recommended for fans of wrestling sci-fi and horror movies. Its nothing new and theres a lot of filler, but its mostly entertaining and it will give you the comic-book and serial inspired Mexican superhero experience you are looking for.
Also, contrary to what the american alternate title suggests, this is not a Neutron movie. While there are some plot similarities between the first three Neutron movies and this one, the movie isnt connected to the Neutron films in any way.
