The world is plagued by mysterious entities that manipulate people's negative emotions, turning some into "seers" but leading most people to die by
suicide once they have seen an entity. A standard prevention method is wearing a blindfold outdoors. In
Barcelona, Spain, Sebastián and his daughter Anna travel together. One day, Sebastián encounters a group of survivors and claims he knows the location of generators that can provide light and heating. Sebastián joins the others in their shelter inside a bus hangar. The next morning, with everyone asleep inside a bus, Sebastián drives it outside and crashes it. Everyone is left without blindfolds; Sebastián slowly leads each to open their eyes, and upon witnessing the entities, they die by suicide. Sebastián is revealed to be a seer and is thus unaffected. Anna congratulates Sebastián on having "saved" the people, urging him to find the other "
lost sheep". Nine months earlier, the arrival of the entities prompted people to flee. Sebastián retrieved Anna but lost his wife in a car accident. They found refuge in a church and met Esteban, a pastor who opined that the entities are angels, and that humanity should be liberated from suffering by embracing death. Sebastián and Anna tried to hide, but one day a group of seers led by the pastor discovered their hiding place and captured them. He forced Anna to open her eyes, killing her. Sebastián then faced the entities, but instead of death, he saw the apparition of Anna, which has accompanied him ever since. Anna tells him he can join his family there when he has "saved" enough people on Earth. Sebastián encounters another group led by Rafa, who has two dogs. Others in the group include Octavio, a Mexican deliveryman with expertise in physics; Roberto and Isabel, a couple; Claire, an English psychiatrist; and Sofia, a young German girl separated from her mother and under Claire's care. Octavio theorizes that the entities are
quantum beings that perceive humans' fear and grief. Sofia shares information about
Montjuïc Castle, believed to be a safe refuge which can be reached by a
gondola lift. The group embarks on a quest to reach the Castle. Rafa dies early on after Sebastián sabotages the dog leashes, and the remainder of the group takes shelter. Sebastián leads Octavio to his death, but begins to doubt the wisdom of Anna's apparition. Roberto and Isabel lose their lives too. Claire suspects Sebastián is a seer and shields Sofia from him. Sebastián, who had started resisting Anna's influence due to bonding with Sofia, vows to protect Claire and Sofia. Meanwhile, Padre and his followers find the trio. Sebastián helps Claire and Sofia get to the gondola lift, then fights Esteban, and they kill each other; Sebastián dies smiling. Claire and Sofia are able to get on the lift and enter Montjuïc, revealed to have been converted into a secret camp for survivors that is overseen by the military. As they are escorted in, Sofia's mother, who also made it to the camp, sees her and the two are reunited. Claire undergoes blood tests by scientists trying to develop an antibody that can provide immunity against the entities' influence. It is revealed that the army has captured one of the creatures and a seer, and are using the seer's blood to try and create an antibody. ==Cast==