'Innes? Innes, it's Isabella. Isabella Velasco...' A simple message on an answer machine. But one that made Innes Haldane's blood run cold. Isabella Velasco was a name from a past that Innes had tried hard to forget. For in 1977 both had spent a fateful year at the Unit, an experimental home for dysfunctional teenagers in Edinburgh. Now, after almost three decades, Isabella is trying to make contact. But before she can reach her, Innes learns that Isabella has committed suicide. And shock quickly turns to fear when she hears that another former patient has also recently killed himself. Has some dark event from 1977 finally come back to haunt them all?