When a priest insists in the Comic-Con International trailer for Fox's "The Exorcist" that demons are merely a metaphor, we can virtually guarantee that all hell is about to break loose.

Inspired by William Peter Blatty’s 1971 horror novel, the upcoming television series is described as a psychological thriller that follows two very different priests tackling one family's demonic possession. On one hand there's Father Tomas Ortega (Alfonso Herrera of "Sense8"), a progressive and ambitious priest who runs a small parish in suburban Chicago. On the other hand -- and on the other side of the world -- is Father Marcus Brennan (Ben Daniels of "House of Cards"), a modern-day Templar Knight who was raised since childhood by the Vatican to wage war against its enemies.

Caught in the middle is the Rance family, seemingly normal members of Father Tomas' parish. However, behind the facade, Henry Rance (Alan Ruck of "Ferris Bueller's Day Off") appears to be slowly losing his mind. Eldest daughter Katherine (Brianne Howey of "Scream Queens") has become a recluse, and younger sister Casey Hannah Kasulka of "The Fosters") claims to be hearing strange noises coming from inside the walls of their house. And, plagued by recurring nightmares, mother Angela (Oscar winner Geena Davis) believes there's a demonic presence in their home that's growing stronger each day. Desperate for help, she turns to Father Tomas, unwittingly setting the naive young priest on a collision course with Father Marcus.

Directed by Rupert Wyatt (“Rise of the Planet of the Apes”), "The Exorcist" is set to premiere this fall on Fox.