The film follows NYPD sergeant Ralph Sarchie (played by Eric Bana), who teams up with a renegade priest, Mendoza (played by Édgar Ramírez), to investigate a series of supernatural events and demonic possessions in New York City.
As Sarchie and Mendoza delve deeper into the mystery, they uncover a connection between the occurrences and a group of U.S. military veterans who participated in a mission in Iraq. The veterans unknowingly unleashed a demonic force during their time overseas.
In the climactic finale, Sarchie confronts the possessed and murderous former Marine, Santino (played by Sean Harris), who is revealed to be the vessel for the demonic entity. Mendoza performs an exorcism to rid Santino of the demon.
During the intense exorcism, the demon attempts to manipulate Sarchie’s memories and emotions, revealing his troubled past. Sarchie fights against the demonic influence and manages to overcome his personal demons.
Mendoza successfully exorcises the demon from Santino, saving him from the possession. The film ends with Sarchie and his family finding closure, and Sarchie realizing the existence of supernatural forces beyond his previous understanding.
The movie concludes on a somewhat hopeful note, emphasizing the theme of redemption and the ongoing battle between good and evil. Sarchie, having faced the horrors of demonic possession, is left with a newfound awareness of the supernatural and a changed perspective on the world.