In the present timeline, Tomas is homeless and living in London, when his shelter catches fire and Tomas passes out from smoke inhalation. Sister Claire, a nun played by Imelda Staunton, rescues Tomas, and after a brief hospitalization, the Sister finds Tomas a place to live in a dilapidated home with Magda (Carla Juri), who is caring for her ailing mother, hidden away in the attic. It does not take long for things to take a creepy turn. Tomas notes bite marks on Magda’s arm, and when he’s working on the house’s plumbing (messed-up pipes in a home is always a bad omen), Tomas uncovers an albino bat in a toilet full of bloody water (when it moved, I may have briefly left my skin).
Nevertheless, Tomas develops an affection for Magda, not unlike the one that he developed for Miriam, although the roles here are somewhat reversed in that Magda has allowed Tomas into her home, and while he is working on it, it is Magda who is caring for him. Tomas soon discovers, however, that the ailing mother is not exactly what she seems.
“I tried to help someone,” Tomas says later to Sister Claire. “They got hurt.” Tomas tells the Sister that he can’t forgive himself for the hurt that she suffered.
This is where the movie shifts. We soon discover that, in the earlier timeline — after Tomas nursed Miriam back to health — he tried to stop her from leaving and crossing the border. When she did, he chased her down and raped her. “They got hurt,” is not an accurate way to characterize the situation. “I hurt her,” would be more apt. Instead of trying to forgive himself, Tomas should have apologized and sought forgiveness from Miriam. He chose, instead, to live with the secret.
This is when we discover that Magda’s ailing mother isn’t Magda’s mother at all, or even a woman. He is a suffering demon who births “tangible” evil in the form of those bloody, albino bats. Magda is the demon’s “companion.”
Soon thereafter, the bigger twists arrive. Turns out, Sister Claire is not a nun at all. She is there to help transform Tomas into a demon for the sins he perpetrated upon Miriam, for which he not only refused to apologize, but refused to acknowledge. Claire asks Tomas who — as a demon — he would like as his “companion,” and Tomas insists that it be Magda, who he has spent so much time trying to free from the control of the first demon. Claire tells Tomas that, in order to make Magda his “companion,” she must free her from the other demon, and so Tomas agrees, believing that by killing the demon, Magda will serve Tomas.
What he does not realize until he kills the demon is that Magda is not a “companion.” She is the pagan deity orchestrating this entire cycle. She punishes evil men for their atrocities by turning them into demonic creatures who feel nothing but pain as they birth evil albino bat babies. Magda has been in control the entire time, and Claire is her human assistant, who brings her evil men to punish.
In the final scene, Magda walks into a convenience store, where she finds Miriam working behind the cash register. Miriam is commiserating about the war, saying that it’s time to move on and forget. “Never forget,” Magda says pointedly, leaving with Miriam the amulet that Tomas unearthed. Miriam, of course, remembers the same amulet from Tomas’ guard shack before he raped her, so the unspoken message here from Magda is clear: “I took care of the man that hurt you.” Back in Magda’s car, meanwhile, Tomas — in the form of a weakened, demonic creature — lives beneath a blanket in the backseat.