Tomy is the most popular kid in high school and is about to turn 13. Tomy and his family are normal, but Boby's family are zombies, and when they turn 13 they turn into zombies, which doesn't happen to Boby, but it does to Tomy.

Tomy, now completely transformed into a zombie, still can't believe what's happening to him. Heidi warns the boys that their mother is a monster hunter and they have to watch out for her. Heidi wants to help Tomy because she's in love with him.

The boys are in the newspaper archives investigating what happened thirteen years ago and why Tomy is a zombie and Boby isn't. Tomy and Boby are upset because they grew up with the wrong families, as a witch switched them at birth.

Garrazimovich bought a monster detector to capture them and gain entry to the lodge. Meanwhile, Tomy and Ricardo are competing to be team captain, and Tomy, being a zombie, has incredible strength, but that could backfire.

When Tomy's parents find out the truth—that he's a zombie, but above all, that he's not their son—they demand answers, blaming Boby's parents for everything. Caro and Heidi will try to calm Chayo and Neto down while they buy time.

Tomy, Boby, Caro, Zaira and Frankie decide to borrow Esmeralda's spellbook to exchange the "zombie for the human" and the "human for the zombie," but they accidentally revive two figures from the past.

Both Tomy and Boby decide to spend a few days at their real families' homes. Now they must try to adapt to new customs and see if they can truly succeed. Meanwhile, Heidi is determined to confess her love to Tomy.

When Zaira tries to get back together with Ricardo, she realizes he prefers to be with Caro. Meanwhile, Garrazimovich discovers there are indeed monsters at the school and decides to hunt at least one, but Heidi makes sure he doesn't succeed.

Tomy realizes he has a very toxic relationship with Lorena and decides to end it. Caro and Zaira throw a party at Zombie Burger to become more popular at school.

Tobias Zeppelin High School organizes its traditional Halloween dance, where some students will take the opportunity to go unnoticed, and others will find a way to be seen for the first time.

When Boby asks Zaira to bring Blanca back to life, Zaira helps him with Esmeralda's spellbook. Blanca has twelve hours to get back to school before she's lost in the abyss forever.

Heidi decides to confess her feelings to Tomy, so she plans a romantic date, but at the same time Tomy will enter into a big dispute as he doesn't know whether to attend the date that Heidi prepared for them or attend American football practice.

When Tomy excitedly gives Heidi some flowers, she denies it in front of Garrazimovich, which makes Tomy very sad. Meanwhile, Lorena sees this as a great opportunity to win back her sweetheart.

When Zeus is momentarily paralyzed, he confesses that Morgana, the same witch who turned him into a zombie, has returned to collect an old debt. The witch demands that he hand over the mythical talisman of Cortés, a powerful totem.

Heidi is turning thirteen and is thrilled because Principal Garrazomovich has let her throw a party at school. Everyone is excited, but Zeus senses something is wrong, and Esmeralda's wand confirms it: werewolf alert.

The wicked witch Morgana, who once cursed Zeus's family in revenge, has returned and now curses Heidi, transforming her into a wolf girl. Now Tomy and his friends must face this new challenge without Garrazimovich noticing.

Esmeralda sees in her crystal ball that Tomy and Zaira could be captured by Garrazimovich, so she brings the families together to see how they can avoid that catastrophic future.

The friends are very excited about the premiere of a movie, but they know that Blanca can't leave the school. Tomy tries to use a spell to get her out, but he fails.

It's Lorena's thirteenth birthday, so Tomy, along with his friends, fears the curse will manifest in her as well. Lorena is happy, but she begins to suffer from inexplicable fits of laughter.

As Frankie is about to celebrate the ninety-fourth anniversary of the premiere of his "grandfather" Frankenstein movie, he is given the idea to emulate the novel and create a creature.

The students at Zeppelin High School are having a rally. The problem is that the teams are made up of six people, so Caro has to be on the popular kids' team, with Lorena, Nina, Ricardo, and the twins.

Lorena and Garrazimovich plot once again to separate Tommy and Heidi, but everything goes wrong and Lorena is discovered. Tommy and Heidi don't give up, as they and all their friends plot to ridicule Lorena, but their plan fails miserably.

The most important event for Garrazimovich, 'La Verbena,' celebrated every year, will take place, but there's a slight problem: it will be a full moon. Because of this, her friends fear that Heidi will turn back into a wolf girl.

Caro just wanted to germinate a little bean to pass Science, but a mistake in the amount with Esmeralda's magic powder turns her pot into Germinio Furibundo, a talking plant with more hunger than manners.

When Tomy and Boby continue their agreement to swap houses every week, conflicts are inevitable: beds that smell like a cemetery, fingernails under the pillow, and arguments over funereal decorations.

Lorena has a new plan to separate Heidi and Tomy; this time she will try to make Tomy jealous by pretending to date Ricardo.

When Caro comes up with the idea of ​​going back in time to prevent Zaira's "Canonical Event" of vomiting on Ricardo, the rest decide to help her go to that moment in the past along with Frankie.

Miss Garrazimovich's punishments drive the children to despair, and fed up with everything, they decide to transform her into a very loving and tender Miss, but they soon realize that the old version of Miss Garrazimovich is the best.

When a new student enters the school, all the girls are shocked by him, as he is very handsome, elegant and polite, but Caro especially is captivated by the mysterious teenager.

Van Helsing arrives at the school in search of monsters, just as Heidi transforms into a werewolf and Caro discovers she's a vampire. Between school projects, failed spells, and mind control, the kids must survive a supernatural night.