Terence Cave, intellectual, music-lover and owner of Cave Antiques, has experienced more than his share of tragedies. His mother's suicide and his young wife's death at the hands of burglars left him to bring up his young twins alone. And now one of them has died in a grotesque accident as a result of bullying. Bryony, the remaining twin, has always been the family's great hope: a golden teenager, in love with her cello and her pony, clever, sweet and eager to please. Now that she is all Terence has left, he realises that his one duty in life is to keep her safe from the world's malign forces, whatever that may take. As he starts to follow his grieving daughter's movements, and enforces a draconian set of rules purely for her own safety, the voices in his head convince him to protect her innocence at any cost. The Possession on Mr Cave is both a nightmare of Gothic proportions and a story of distorted love, with chilling resonance for anyone who has been a parent or a frustrated teenager. In this compulsive novel, the characteristic black humour of The Last Family in England and The Dead Fathers Club moves even further onto the dark side. Matt Haig lays bare the process by which Terence's love for Bryony becomes a possessive force that will lead to destruction and, ultimately, murder.