Line Of Duty

BBC1, Sundays, 9pm

There’s a moment in episode two of the new series of Line Of Duty when beloved Superintendent Ted Hastings (Adrian Dunbar) sternly says, “There’s only one thing I’m interested in, and that’s catching bent coppers.” It’s a sentence he’s uttered many times before during the previous five seasons, and fans of the show will get an instant thrill of recognition as the words tumble from his mouth. So, even though Hastings is being utterly sincere and deadly serious, it’s also funny. You could even call it “fan service” – a little nod and wink to those of us who’ve watched every episode so far, possibly multiple times. And yet it makes total sense, because Ted is the kind of guy who does repeat himself on a regular basis, and it’s partly why we love him so. In fact, in this new series, Hastings seems to be the only constant. Everything else is in flux. Writer Jed Mercurio has shaken things up, so key characters are not in their usual roles, and even if they are initially, it’s not long before they’re undermining any sense of certainty (yes, I’m being deliberately vague here to avoid spoilers). And in the case of new series guest lead Kelly Macdonald’s DCI Joanne Davidson, she is shrouded in so much mystery – an enigma wrapped in a riddle, encased in layers of doubt and paranoia – she’s already one of most fascinating characters in the history of the show. We’ve now reached the ultimate sweet spot in this unparalleled saga, where every major character has reason to distrust every other major character, and it’s a constant, visceral thrill to watch it all unfold. Turns out catching bent coppers makes for some of the greatest TV drama.