Agnes never wanted to move to Collyer House, a crumbling old mansion-turned-psychiatric hospital. But she’s supposed to be cataloguing the house’s vast library . . . If only she could tear herself away from one book in particular. An intriguing old diary, penned by the house’s former mistress. Its pages warn of a sinister black dog, which appeared just before the writer’s daughter died. Now history seems doomed to repeat itself. Young mum Tina-Marie turns up at the hospital, raving of a black dog that follows her every step. She just knows it’s a bad omen. That something terrible is about to happen to her vulnerable young daughter. The next day, Tina-Marie drags herself back to Agnes’s door, a stab wound gaping in her chest. She opens her mouth to speak . . . but nothing comes out. Only one last rattling breath. Tina-Marie’s beloved daughter is nowhere to be found. Agnes will stop at nothing to bring her home safe. But that same night, Agnes is woken by growls in the dark . . . A gripping, sophisticated crime mystery that will have you intrigued from the first page. Steeped in the intoxicating atmosphere of Central London, from the twisty alleys of Soho to the grimy towpaths of Kings Cross.