While his professional standing hangs by a thread, Grace, back on active investigations, tackles four impossible cases. A sadistic serial killer on the South Coast, a wealthy entrepreneur who insists he's innocent of his wife's murder, a skeleton unearthed in a storm drain and a dead body in the Channel, all test Grace's instincts. When an old rival arrives at East Sussex CID, Roy finds his reputation tarnished again, while, on a personal front, an unexpected new connection offers a chance at happiness. Can Grace take a shot at moving on when part of him still clings to the past?