04/04/2021 05:00 BST Line Of Duty Cast: A Guide To Who’s Who In Series Six And Where You’ve Seen The Actors Before If your head hurts from trying to work out who everyone is and what else you've seen them in, we're here to help. Watching Line Of Duty can be tricky at the best of times. If you’re not working out subtle references to previous series, you’re wondering who is who and whether they’re a “bent copper” or not – not to mention trying to remember where you’ve seen all of the actors before. Well, we’re here to help... at least with some of that, anyway.