In William Peter Blatty's 1971 novel, Father Damien Karras was one of the priests who exorcises the demon from young Regan MacNeil.

Karras dies by throwing himself down a flight of stairs in order to purge the demon from his own body after having coaxed it out of Regan's.

While incarcerated there, the spirit suppresses Karras's personality and makes forays into the bodies of other patients in order to commit a series of ritual murders.

He assists Wala Kitu and Eigen Vector with nothing before double-crossing them and getting shot to death by the villain, John Milton Bradley Sill.

[3][4][5] John Ward, the main protagonist of Faith: The Unholy Trinity is inspired by Karras and his appearance is based on Jason Miller’s portrayal of the character in the 1973 adaptation.