Line of Duty creator, writer and showrunner, Jed Mercurio, and leading cast member Martin Compston, aka DI Steve Arnott, enter the interrogation room, press the record button, and once the famous beep has signalled, it is time to begin as they grill each other on their personal memories and experiences of being assigned to the BBC’s record-breaking cop corruption series. How did Martin get cast in the first place? What is Jed’s approach to the writing of each series? What are their thoughts on the show’s phenomenal success? And is the work of AC-12 really over, or will Martin ever need to be fitted for a new waistcoat, worthy of a return for a potential new series?