The merciless III : origins of evil
(Book)

Brooklyn knows that there's no good without evil, no right without wrong. And when a helpless girl calls her teen helpline, whispering that someone is hurting her, Brooklyn knows that she needs to save her anonymous caller, even if it means doing something bad. Her parents and friends assure her the call was probably a prank-but Brooklyn has always had a tendency to take over, whether someone has asked for help or not. She discovers the call came from Christ First Church and finds herself plunged into the cultish community of its youth group. She's especially drawn to Gavin, the angelic yet tortured pastor's son. Torn between an unstoppable attraction to Gavin and her obsession with the truth, Brooklyn is forced to make a devastating choice to rid Christ Church of evil once and for all. . . . But the devil has plans for Brooklyn's soul. -- from Amazon.