Pitch Black (Black CATs #2)
Leslie A. Kelly

Samantha Dalton didn't set out to become an online vigilante, until her grandmother was swindled out of everything she owned. Devoting herself to exposing fraud and preventing tragedies from happening to other families, Sam has gained fame and success with her website and a recently released book. A hermit since her ugly divorce, Sam really doesn't want the outside world intruding on her privacy. Especially not when that outside world is a sexy FBI agent who tells her she has a cyber connection to a murdered teenage boy.
When the killer opens a line of communication with Sam via her website, Alec and his team enlist her help to stop him. There's one thing they don't know, however. The Professor doesn't just see Sam Dalton as an anonymous online foe. He is, in fact, her number one fan. He's been watching her, waiting for the time to be right to make his move. He just isn't sure what that move will be.