from the back:

Vicar Obadiah Demurral isn't satisfied running the affairs of his village--now he wants to control the world. And if his plan works, he will obtain a weapon so powerful, even God and his angels will fall down at his feet. Demurral will stop at nothing, and as a shadowmancer--a sorcerer who speaks to the dead--he even commands restless souls to do his bidding. Who will stand against him? Raphah has come a long distance to reclaim the ancient relic Demurral has stolen--dangerously volatile in the wrong hands--but Raphah is young. Even younger are Thomas and Kate, accidentally drawn into this war between good and evil. Their struggle against Demurral will bring them face-to-face with the powers of darkness in an epic battle...and the world holds its breath.