The film [actually a serial] is EL ENMASCARADO DE PLATA and was written by Jose G. Cruz who was doing the comic book EL SANTO. However apparantly El Santo had cold feet about doing the movie and rather than wait for Santo to "man up" and do the movie the filmmakers instead offered the role to white masked El Medico Asesino [The Murderous Medic] another popular masked heel. The serial retained the original title and to justify it's use the filmmakers added a second masked villain to the serial called El Enmascarado de Plata [The Silver Masked Man] who is killed off halfway into the serial, and then the serial's "True" villain the masked El Tigre takes over the evil doings. In yet another confusing twist El Medico is seen later in the serial wearing one of his masks now spray painted silver. Go figure. It's hard to say why El Santo backed away from the serial, which is actually quite good despite what some people think, and later wound up doing two lesser films in Cuba. Perhaps his buddy Fernando Oses, who also appears in the Cuban films, convinced him it was a good idea to be making movies.

On a side note in 1972 "El Medico Asesino" once again replaced El Santo in yet another movie role he turned down, THE CHAMPIONS OF JUSTICE, except it isn't Medico Asesino, who passed away in the early 60's. This time around Rogelio Agrasanchez hired Gran Markus to fill out his cast of lucha libre superhero team and just billed him as Medico Asesino.