The tragic high profile crimes which inspired Line of Duty Fans may be surprised to learn that Line of Duty has been inspired by some of the nation's most hight profile - and tragic - criminal cases. Subscribe When you subscribe we will use the information you provide to send you these newsletters. Your information will be used in accordance with ourPrivacy Notice. Thank you for subscribingWe have more newslettersShow meSee ourprivacy notice Line of Duty fever is back with the hit BBC drama cop series shocking fans with incredible cliff hangers and plot twists. Starring Martin Compston as DS Steve Arnott, the popular series delves into the world of police anti-corruption and revolves around discovering the identity of "H".