In Tess Gerritsen's chilling thriller, 'The Mefisto Club,' Boston medical examiner Maura Isles and detective Jane Rizzoli confront gruesome murders with terrifying satanic overtones. The investigation leads them to a secretive society, The Mefisto Club, dedicated to confronting an ancient evil they believe is a literal demon. As Rizzoli and Isles delve deeper into a world of dark rituals and hidden history, they must confront an adversary whose evil seems to transcend the human realm, forcing them to question everything they believe about the battle between good and evil.