Santo vs. the She-Wolves aka Santo contra las lobas opens with a young blonde woman is drawn to an abandoned warehouse by a disembodied voice saying “Come…come…” She is confronted by a hairy old woman, who says she is Luba, queen of the werewolves. It is time for her to be reborn in a new body; then the werewolves will destroy the human race and rule the earth. The blonde stabs old Luba and becomes queen; she is carried around joyfully by her subjects.
There is a nice matched cut from a werewolf howling over the body of old Luba to a screaming crowd watching Santo wrestle. After the match, the young Luba visits his dressing room, claiming she’s a big fan and would “like to get to know him better”. Santo puts her off, and then gets another visitor: detective Jaime Pons, who says he was hired by the Harker family to contact him, concerning werewolves. Santo is dubious, but he accepts an envelope from Pons with instructions about meeting César Harker.
Later, as Santo starts to leave the darkened arena, he is pursued by several “wolves”. After a brief battle in the ring, Santo leaps up and hangs onto the light fixture, shouting for help! When the arena security guards arrive, the wolves are gone, and they think Santo is a bit crazy!
Meanwhile, Pons, on his way back to his hotel, is hailed by the bloody Luba. She gasps that she was attacked by werewolves. They go back to his room, where he gives her a drink. However, as they start to get “better acquainted,” Luba turns into a werewolf and chases Pons around before killing him.
In his apartment, Santo is surprised when a wolf jumps out of the closet, but it promptly disappears. This makes him decide to follow up on the Harker connection. The next day, he meets César Harker at a hotel outside the city. As they speak, a young woman swimmer cries for help from the pool. César leaps in to save her, but she tries to drown him, so Santo has to jump in and knock her out. They drag her out of the pool, but she disappears when their backs are turned. Harker tells Santo that his family has battled the werewolf race for generations, but it is foretold than only a “silver symbol” can destroy them for good, and that means Santo.
Santo agrees to help, but first he has to participate in another wrestling match. While this is going on, César is slain by werewolf Luba on his hacienda. His workers pursue the wounded werewolf woman, and retrieve her body when she finally drops dead. Gypsy Ana tells Julieta, a neighbor of the Harkers, that the queen of the werewolves is dead; Julieta orders her daughters Adriana and Eloísa locked up.
Santo takes a train to the town near the Harker hacienda. The stationmaster shows him a big box that recently arrived from Transylvania–but it has no delivery address. Later that night, a band of werewolves steals the box from the station. They open it at a ceremony, revealing Licán, King of the Werewolves. He says the first order of business is to choose a new queen.
Santo and Gitano (the servant of Dr. Marcus, brother of Julieta) are chased away by the villagers for asking too many questions. They throw stones and shoot at Santo.
Present at the funeral are Eric Harker, César’s twin brother, Marcus, Adriana, and Eloísa. Eloísa tells Eric that she thinks she’s a werewolf, since she remembers the death of the stationmaster when the box was stolen. Meanwhile, Marcus informs the local police that the werewolf woman who killed César had been dead for a month.
Licán visits Marcus, claiming that he is a scientist studying evolution. He invites everyone to a dinner party at his house; Marcus declines, but Santo, Eric, Gitano, Adriana, and Eloísa go. The party seems friendly, but after a while some of the guests turn into werewolves and attack everyone else! The protagonists make their escape. Back at the Marcus residence, Santo finds Marcus half-changed into a werewolf. He says his family is cursed, but he’s a good werewolf. Santo–for some reason–will also change into a werewolf if he doesn’t destroy Licán by the night of the Great Red Moon – the next night!
They prepare for an assault by the werewolves, handing out rifles to the workers. They try to send the children away in a station wagon driven by Adriana, with Gitano riding shotgun, but the werewolves ambush the car with big rocks and flaming bundles of brush, forcing them back to the hacienda.
That night, the werewolves attack. Julieta turns into a werewolf and threatens Adriana and Eloísa, but Santo intervenes and kills her with a bodyslam. Santo: “She was the queen of the werewolves.” He then takes off after the king, Licán, who runs a long way until Santo finally catches him and throws him off a cliff, just as the sun rises – finally lifting the curse!