Leo returns to work after his recovery from a life-threatening head trauma. His first big case involves a young woman, Ruth Gardiner, who apparently jumped off the roof of a derelict tower block. He soon begins to notice that it may not be a suicide. The investigation reveals that the dead girl may have been an informant for an undercover cop, leading Leo wondering if there is a cover-up underway. He is contacted by Danielle, the girlfriend of a rogue undercover detective, whose life is in danger and the situation begins to escalate.