Angela Rance suspects a demonic presence has entered her home, and enlists the help of Father Tomas Ortega, who calls on experienced exorcist Father Marcus Keane.

Tomas and Marcus seek permission from papal emissaries to conduct an exorcism, only to be met with shocking news, while Casey exhibits odd behavior.

As Casey's condition deteriorates, Marcus is sent on an eye opening mission, and Tomas receives an unexpected visit.

As the exorcism begins, Tomas and Marcus engage the demon in spiritual warfare, with the pressure of the process driving a wedge between the Rance family.

The Rance family is engulfed in a storm of publicity, while Marcus' search for Casey leads him into the terrifying underbelly of the city.

Marcus asks for assistance from Mother Bernadette, while Tomas has a crisis of conscience, and Father Bennett's investigations lead him into danger.

Tomas, Marcus and Mother Bernadette race against time to defeat the demon, and the Rance family find themselves drawn into the conflict.

Tomas is offered a life changing opportunity, Marcus makes a shocking discovery, and a new threat to the Rance family emerges.

The demon is determined to destroy the Rance family, while the enemies of the church mobilize against Pope Sebastian.