Former OFW Mario drives his daughter PJ, a senior-year medical student, to San Lazaro University, hoping to bridge a strained relationship that has lingered since PJ’s mother suffered a fatal stroke. The trip sets the stage for a tense new chapter as PJ steps into campus life with a mix of duty, ambition, and lingering grief.
At the university, PJ reconnects with her Block Z block mates, including Erika Erika and Myles Myles, alongside basketball captain Lucas, a talented player who quietly harbors feelings for her. The day unfolds into a routine of class, camaraderie, and the everyday pressures of medical training, but danger is already brewing outside the walls of the campus.
After dropping PJ off, [Mario] accidentally hits a pedestrian and brings him to the university hospital where PJ and her friends work. Inside, [PJ] and Erika tend to Angie, who carries a bite wound and suddenly experiences a seizure before dying. PJ consoles Angie’s young daughter, Ruby, as the situation grows more alarming. As Myles and fellow student Gary move Angie’s body toward the morgue, the situation takes a horrifying turn: Angie reanimates, bites Gary’s neck, and chaos erupts. The hospital and campus quickly become ground zero as Angie’s infection spreads to staff and patients, then to students and personnel on campus.
Lucas, whose basketball team is incapacitated by the outbreak, meets with [Mario] and the pedestrian. The pedestrian is bitten and turned, forcing the two to kill him and then split up to search for PJ. The military soon encloses the university, launching a quarantine that savagely targets both zombies and fleeing students. Amid the emergency, student council president Gelo and his father, a general, orchestrate helicopter evacuations for him, a plan that he partly reveals to Vanessa. Vanessa privately informs the rest of the council, heightening the tension as loyalties fracture under pressure.
The five—PJ, Erika, Myles, Lucas, and Gelo—flee together through a city spiraling into panic as the undead surge toward every exit. A heated argument between Gelo and Vanessa ends when he pushes her down a staircase, killing her in front of PJ’s group. To protect himself, Gelo lies, claiming Vanessa was infected, and secretly remains with the survivor group.
They push on toward the hospital, then toward the church where [Mario] has found shelter with Ruby and Bebeth. Bebeth, a security guard, becomes a vital ally as the group contends with the overwhelming zombie threat. Gelo reveals that the helicopter can only carry two people, prompting a desperate debate about who should board and who must stay behind. In a tense moment, Ruby spots her mother, causing pandemonium as a wave of the undead closes in. Ruby is devoured, and Gelo seals himself inside the faculty building, leaving the others to run.
The survivors regroup in the dormitory, and PJ and [Mario] rekindle a difficult reconciliation. Mario is bitten by a zombie and, with a heavy heart, urges the group to kill him. They lock him in a closet and say their final goodbyes as they evacuate toward the roof. One by one, the group falls away until only PJ remains, reaches the helipad, and then collapses from exhaustion.
When PJ awakes the next day, the helicopter has not appeared, and a bite on her hand confirms she is immune to the virus. She fights back through the dorm to reunite with [Mario], who is also immune, and the two emerge into a city already altered by the outbreak. They descend through an ancient tunnel beneath the church, a path Ruby had previously found, and slip out through a manhole while avoiding the delirious Gelo, who has been abandoned and is now a danger to himself.
PJ and Mario realize the infection has spread beyond the campus and arm themselves for the new world. News reports reveal a surprising vulnerability of the undead to water, and Bebeth broadcasts a message of survival from the survivors who remain. A typhoon arrives, weakening and destroying many of the zombies, offering a fragile glimmer of hope. Two weeks later, a small band of survivors discovers Lucas, badly injured, and takes him in, suggesting that not all is lost even as the city reels from the crisis.