English detective DCI Alan Banks returns in this fourth series of the popular crime drama with three new, original stories. In What Will Survive, Banks struggles to cope with the sudden death of his mother, as he investigates the murder of a young Estonian woman and the disappearance of her drug-dependent sister. In Buried, he must navigate difficult emotional territory when the body of an eminent lawyer is washed up in an underground river and he suspects a member of her grieving family is responsible for her death. In Ghosts, the body of a university student is found dumped in a ravine. His friends claim he was a model undergraduate, but officers Annie and Ken soon discover that he had a double life manufacturing ecstasy.