Santo vs. The TV Killer aka Santo contra el asesino de television opens with a TV broadcast featuring a large ranchera singer Gerardo Reyes who is interrupted by a masked man, Magnus, who says he is going to show “an authentic criminal act,” the live kidnaping of actress Marina Laval. And he does. Then he says, tune in next week for the broadcast of a jewel robbery. The police are puzzled: time passes, and no ransom demand is forthcoming. Gerardo Reyes is also a newspaper reporter who attends Insp. Fierro’s press conference; Pedro Grandet, another reporter, suggests that he and Gerardo pool their information.
As always, only wrestler-superhero Santo can help!
During the broadcast, Santo and his manager Carlitos are driving back from Durango–their car radio suddenly goes haywire. Back in the city, Santo and Ham Lee team up to defeat El Escorpión and Cobra. Then they are called in by Fierro, to help with the case.
Magnus tells Marina that he was captivated by her beauty and that’s why he kidnaped her. Gerardo and another man break into the house where Magnus was hiding, but the villain and his victim are gone. Gerardo reports to his editor at “El Sol de México;” female reporter Diana demands to be assigned to the story, since she knows Santo and can get info from him. The editor agrees, but tells Gerardo to keep an eye on her.
Held prisoner in a cavern where Magnus has his headquarters, Marina is refusing to eat. Magnus says he doesn’t really love her: Marina’s mother once double-crossed him and reported him to the police for smuggling, so he had to leave Mexico. He became rich as an arms dealer, now he’s back and has kidnaped Marina to make her mother suffer. If she starves herself, so much the better. Then you don’t love me, she asks. “I only love Magnus!” he replies.
Magnus makes good on his boast to broadcast a jewel robbery, despite the efforts of the police to stop him. His next crime, he says, will be the kidnaping of singer Brenda Durán. Brenda moves in with Santo for protection. Diana is suspicious and maybe a little jealous. She’s also mad at Gerardo for following her. On the night Brenda is supposed to be kidnaped, she performs at a nightclub. Some of Magnus’s henchmen kill the lights and attack the stage, but Carlitos turns the lights back on and Santo defeats the men.
However, two men dressed like cops take Brenda out of the club. A machine mounted in the rafters emits a loud noise that paralyzes Santo and Fierro. In the parking lot, Carlitos battles the fake cops so Gerardo can rescue Brenda, but Diana sneaks into the villains’ car and they drive off with her instead. Magnus makes a broadcast, saying his crime was successful. Gerardo points out that this must be a tape, since Brenda was rescued. But then, apropos of nothing, Gerardo says “He has her in his power and I have to save her,” presumably referring to Diana, but up to this point nobody knows she has been captured!
Later, Magnus announces that he has Diana in his power, and that Santo will die during his next match. He offers El Asesino del Ring one million pesos to kill Santo. Meanwhile, Santo and Gerardo, flying in a helicopter, have located some TV microwave dishes in the desert, near where Santo’s car radio went bad during the first broadcast. They plan to return later.
That night, Santo meets El Asesino in a very brightly-lit arena in front of a couple of hundred spectators. An automatic machine gun in the rafters opens up but kills El Asesino instead of Santo, and Gerardo puts it out of commission with a pistol shot.
Gerardo and Santo go to Magnus’s hideout, knocking out a bunch of guards. However, Magnus threatens to kill Diana and Marina, so Santo surrenders. He is tied to a metal pole, and Magnus prepares to broadcast his death, by burning him at the stake. But one of the TV viewers is El Mago Yeo, who concentrates hard and makes the handcuffs drop off Santo’s hands! Santo defeats the villains, aided by Diana and Gerardo.
Magnus is revealed to be Pedro Grandet. He sets off explosions which destroy his hideout, but Santo and his friends escape. The explosions are well-done, but this sequence is marred by some mis-matched shots.
As the film ends, Santo, Gerardo and Carlitos join El Mago Yeo on stage for his act. Carlitos is placed into a a trunk and made to disappear!