Every Last Devil (DCI Kett, #16)

While filming a school project inside a ruined church, three teenagers make a horrific discovery: a severed head, left as part of a demonic ritual.

Before they can call the police, they are brutally attacked—and one of the teenagers is taken.

DCI Kett and the Extreme Crime Task Force know it's only a matter of time before the missing girl meets a terrifying fate. But as they hunt for her they find themselves caught up in one of the most dangerous cases of their careers—a living nightmare of conspiracy, sacrifice and cold-blooded murder.

Kett must explore the darkest parts of the country, the human soul, and himself to get to the heart of this unholy mystery.