A new school term begins with Martin as Academic Director, the investigative teens brought to heel through infection, and a monster in the surrounding woods.
Both Maria and Lucas find themselves disbelieved, one for claiming the birth of a son and having her life threatened, the other for reporting a werewolf in the woods that infiltrates the school by night.
A mix-up in bottles exposes the fact of a mole among the teens, but it also leaves Ivan without his daily dosage. As Jacques and Hugo seek the identity of the invasive killer creature, Lucas lays hands on Jacques' cash.
At the school's Feast of Saint Isabel, as Jacques continues to deprive Ivan of medication, Ivan, rather than give up Maria, aims literally to take his dad down during the festivities and expire together.
Hugo begins to understand the wolf man in the woods, Jacques finds his authority undermined, and the teens help Julia face the powerful Paula-like girl ghost.
As knowledge is power, factions play a three-sided chess game (figuratively) for more. Evelyn, meanwhile, fears she's pregnant, while Carolina seeks the identity of the mole.
Carolina's disappearance freaks out her friends as different stories roll in about her sudden departure. They're sure of one thing - Jacques is behind it.
As Marcos mourns the loss of Carolina, Rebeca recruits Maria into a dangerous plan, much against Fermin's wishes, and Martin encounters a familiar face he's never met.
Eva's clue leads the teens to discover a sealed bedroom, Fermin fumes over Rebeca getting Maria more deeply involved in intrigue, and the kids hope to get Jacinta "laid."
With only two factions aware, a countdown barrels toward the activation of lethal biological bombs loosed upon world society. Meanwhile, the kids find Hugo to be magical.
The wrong determination on which twin survived the night, Hugo or Daniel, could cost lives. Meanwhile, as Marcos works to remove Paula from school, Elsa threatens to blow Alicia's cover if her demand for justice isn't met.