Demon Knight

An exiled priest. A demonic knight. The war between heaven and hell has begun...Once the Chief Exorcist for the Vatican, Blake Rossi was thrown out of the church when an exorcism ritual went horribly wrong. And he's been haunted by his failure ever since. Now Blake wallows in guilt, and drinks himself to sleep every night.
But the former priest knows there are people still plagued by evil. People who need his help. When an old friend offers a chance for redemption, Blake agrees and becomes a freelance exorcist.
After traveling to California to help a reclusive old woman banish an ancient demon, Blake discovers his new career may be more dangerous than he originally thought. Years ago, this demon-a powerful knight of hell-was trapped by the woman's father. Now it roams free, gathering an army of demonic soldiers to claim its bloody retribution.
The forces of hell have been unleashed...
And an exorcist with a tortured past is the only thing standing between them and millions of innocent souls.