Karla (represented by Troika), stars as Detective Sergeant Nancy Devlin who has a secret double life. Her exemplary police career masks a covert attachment to shady businessman and drugs trafficker, Frank Le Saux (Philip Glenister). Inextricably linked to Frank from childhood as the father of her best friend, Hayley, played by Laura Haddock, and the father figure she herself craved.
Nancy has been playing a dangerous game to ensure that Frank always remains off the police radar.
Nancy soon finds herself at the centre of an investigation which puts her at risk of exposure and sees her stalked by a killer intent on destroying her. Nancy’s complicated love life and relationships with colleagues creates further tension as she doesn’t know who she can trust..literally with her life.