Martin Compston
The Scottish actor plays English police officer DI Steve Arnott, and has admitted he's "not naturally good at accents".
Is this the end of the road for AC-12?
And they sound every bit as intense to film as they are to watch.
We'd only just managed to calm ourselves down after Sunday night's thrilling ep.
We've uncovered all the secrets of AC-12 – because Hastings and co aren't the only detectives round here.
The cast are currently filming the sixth series, after production resumed last month.
He plays D.S. Steve Arnott in the hit crime drama.
And of course, Phoebe Waller-Bridge was responsible for three of them.
Line Of Duty Writer Jed Mercurio Labels Journalist A ‘C***’ For Writing ‘Lies’ About New Series Cast
The BBC drama's showrunner didn't hold back.
Just wait until you hear Vicky McClure's 'H' theory.