Close friends Wyatt and Christian, once inseparable, drift back into each other’s orbit in the bustle of New York City. Wyatt has withdrawn after a painful breakup with his fiancée, while Christian, also newly single, masks his insecurities with sculpted muscles and a pushy, aggressive bravado. As they reconnect, [Christian] invites [Wyatt] to stay at his apartment and even schemes a little social nudge: he asks Mara, his supervisor, to invite a friend along on a date.
They arrive to find that Sandy, Mara’s friend, has fallen and hurt herself. [Wyatt] examines [Sandy] and suggests she go to the hospital. The trio spends the evening waiting together, and when [Mara] walks [Christian] to the subway, he falters at a kiss goodnight. [Wyatt] reassures him that Mara is likely still interested, despite how the night ended. After [Christian] falls asleep, [Wyatt] receives an anonymous call—an indistinct voice urges him to flee the city and prepare for a demonic invasion.
Seeking clarity, [Wyatt] hauls his fears to a session with a psychiatrist—but the moment the discussion shifts toward potential possession, [Wyatt] becomes convinced the psychiatrist himself is tormented by demons. Meanwhile, [Mara] and [Christian] continue seeing each other, while Wyatt’s phone calls grow increasingly ominous, now speaking in [Mara]’s voice and warning of apocalypse and the demonic contagion that can inhabit human hosts. He hoards weapons in [Christian]’s basement and wrestles with thoughts of suicide and the urge to harm those he suspects are possessed.
In a surprising turn of confidence, [Christian] believes a promotion might be coming his way, until a cruel reality check arrives: he has been fired. A message on his computer, signed by his coworkers, calls him an asshole. He returns home to find [Wyatt] waiting, and soon [Mara] visits too. The three share uneasy, tense conversation; [Wyatt] pushes for more information about the invasion, probing for answers about the voice he heard. When [Mara] realizes how serious [Wyatt] is, she bolts. [Christian] returns, disappointed that she left, and [Wyatt] grows increasingly agitated, ranting about the approaching apocalypse.
To help, [Christian] arranges a course of psychiatric care, while [Wyatt] confronts Mara in a moment of remorse—she defends herself and injures him. Yet, with remorse in her eyes, she also helps him clean up, even as [Wyatt] is horrified when she suddenly transforms into a demon. Panicked, [Wyatt] escapes and finds [Christian] preparing to join an effort to confront his own insecurities on a broader scale. He urges his friend to leave the city and brace for the oncoming apocalypse, on one condition: [Wyatt] will attend the psychiatric appointment.
As the apocalyptic signs mount, [Wyatt] becomes convinced that [Christian] is possessed and prepares to kill him as he watches the other man transform. In a crucial moment, the vision peaks and [Wyatt] realizes he is hallucinating; recognizing the humanity within [Christian], he frees him. In the aftermath, [Christian] notes that he has finally faced his fears by confronting death, and the two close in a quiet, relieved embrace.
