Ridley is an utter waste of Adrian Dunbar

He’s a national treasure, a beloved on-screen copper, and an actor who, thanks to Line of Duty, has turned “Jesus, Mary and Joseph and the Wee Donkey” into a wildly-popular catchphrase. He is Adrian Dunbar, a star who somehow combines the surreal affability of Father Ted with the take-no-prisoners intensity of Dirty Harry. We would watch him in anything – though, his latest series puts that theory sorely to the test.

“Trigger warning” and “Adrian Dunbar” aren’t words that typically go together, but that’s what we’re dealing with in the star’s sleepy police procedural, Ridley. Halfway through the first episode of the new season, the action cuts alarmingly to a jazz club where Dunbar’s consulting detective Alex Ridley is on stage crooning his heart out, like an AliExpress Frank Sinatra.

A singing detective? On a Sunday night on ITV? What’s going on? The answer is Ridley is part-owner of the club, where he sidelines in entertaining unsuspecting punters. It’s quite the twist – at least to newcomers to this otherwise plodding and predictable whodunit.

Every episode is cosy crime meets cosy crooning, as our low-key protagonist ends up at Marling’s jazz club, belting out a song. He’s a decent singer, so it isn’t as if he is murdering the tune. And, in fairness, it’s a daring departure from the small-screen detective formula. (Imagine if Inspector Morse was a happy house DJ in his spare time.) But Ridley’s commitment to thinking outside the box ends there. Sadly, it otherwise goes through the motions like a bored beat cop waiting for his shift to end.

Worst of all, it wastes Dunbar and the folksy fizz he brings to Line of Duty in his capacity as upstanding Superintendent Ted Hastings. As retired copper Ridley, he’s the very opposite of his no-nonsense Ted, and the antiseptic anti-hero is an ill fit with Dunbar’s natural charm.

Honestly, it’s grim stuff. Ridley’s backstory is that his wife and daughter have been murdered off-screen by a serial killer and that he’s dealing with the pain by taking a gig economy job as a consultant to the police. It makes a difference from the usual hard-drinking detectives with messy marriages, but it does require Dunbar to potter around joylessly – which seems to be missing the point of having him on screen.

The show just doesn’t appear to appreciate the qualities that have propelled Dunbar to such treasured status. Yes, we know he can sing – one of his break-out roles was playing Irish tenor Josef Locke in 1991’s Hear My Song (he co-wrote the script). However, his greatest talent has always been to bring pizazz and humanity to otherwise unremarkable protagonists, particularly in crime shows – as he proved with memorable guest turns in Cracker and Inspector Morse.

He was the bottom-of-the-credits actor who always made you pay attention. He went one better with Line of Duty, where Ted Hastings became perhaps the most beloved of the characters, without Dunbar ever hogging the screen or trying to overshadow the rest of the cast. He’s just great to watch.

Ridley’s plot hardly lets Dunbar shine. Ridley, aided by DI Carol Farman (Bronagh Waugh), disentangles the mystery of a jewellery heist gone wrong. But around and around the plates spin – the near two-hour run-time simply doesn’t justify a clunky story with enough red herrings to make a three-course meal.

Normally, Dunbar’s charm would have compensated for a silly, over-stuffed storyline – look at the wonders he worked on Line of Duty. Yet, even by the pulpy standards of an ITV whodunit, Ridley is an unconvincing creation. There is, in particular, a constant tension between the show’s insistence that he is a sympathetic grieving dad seeking closure and his flagrant willingness to put protégé Tasha (Chloe Harris) in harm’s way to solve the case.

I’m not sure Dunbar is entirely sold on Ridley, either. He has the mooching energy of someone whose batteries could do with a recharge. The only time his performance comes alive is when he is singing at his jazz club – but even with the novelty of Ted Hastings rocking an open mic night, there is little in Ridley worth making a song and dance about. What a waste of two hours – and what a misuse of the wonderful Dunbar.

‘Ridley’ season two continues next Sunday at 8pm on ITV1