Not only does McDonald & Dodds offer up a unique sleuthing partnership, it touches on contemporary issues - as a good detective drama should, says Jason Watkins. It's important we acknowledge both in popular television, he tells Gemma Dunn.

Jason Watkins has made a career out of playing peculiar and complex - often misjudged - characters.

Take his Bafta-winning lead in the hit drama The Lost Honour Of Christopher Jefferies, his turn as forensics nerd Tim Ifield in Line Of Duty, or his recent run as former prime minister Harold Wilson in season three of The Crown, for instance.

Then there's the comedy: supermarket sitcom Trollied, in-house satire W1A, as well as a movie repertoire which includes everything from Nativity! (who could forget camp wedding planner Gregory Hugh?) to an adaptation of Ian McEwan's The Children Act. The list goes on.

Put simply, he's brilliant at what he does. And it's all down to good choice.

"You try and get a bit of contradiction in characters, because we're all contradictory as people," he says at the launch of his latest project.

"Certainly in plays - I used to do a lot of plays when I was younger - you'd try and find the anachronism in your character which is completely different to what you were seeing. I think audiences get drawn into that."

His latest role fits the bill perfectly.

Watkins, 53, will takes a title role in McDonald & Dodds, ITV's brand-new detective drama, which focuses on a series of feature-length crime mysteries.

Set in Bath, the two-parter - created by screenwriter Robert Murphy - pairs the wildly ambitious DCI McDonald (Cold Feet's Tala Gouveia) with the shy, modest DS Dodds (Watkins).

While McDonald - described as a driven, battering ram of a cop - has transferred from the "mean" streets of south London, Dodds is quiet, unassuming and enigmatic. Though thrust back into frontline action for the first time in a decade, he discovers a hidden talent for deciphering puzzles.

"It's just presumed that he's a bland, beige, middle-aged man and yet he's got a bit of something about him - a spark that's been neglected," Watkins empathises.

"And because of this rather unlikely and improbable coupling [with McDonald], he's starting to see a different side of himself. A world that he boxed off."

It explains the drama's working title, Invisible, which was initially a chance for writer Murphy to explore the idea of a "presence people don't see".

"Dodds is invisible in the sense that people don't notice him. He's that person in the corner who doesn't put himself forward," explains Watkins.

"I'm not criticising social media - I'm a big social media person myself - but sometimes you think, 'The person who shouts loudest gets noticed'. Yet there are lots of very interesting, brilliant people who don't feel the need - or aren't able - to compete in that environment and are just as valid as everybody else.

"That's where Dodds sits," concludes the Shropshire-born actor. "He's the guy at the back with his hand up going, 'Excuse me, I've just found this amazing thing out that solves your case'. I love that."

So it turns out that being thrown together with seemingly nothing in common is just the trick then, as McDonald and Dodds forge a rumbustious, entertaining and ultimately - give or take a few setbacks - effective partnership.

"This is a cop drama that is in some ways ground-breaking in the relationship between McDonald and Dodds," Watkins asserts of the unlikely duo. "It's great entertainment for the audience, but also it does touch on real issues today.

"McDonald is a thruster; she might be slightly impatient, but she certainly runs up against the old prejudice against her as a young black woman from outside this area [and] that's what she is fighting against."

Elaborating, Watkins adds: "It's not explicit, but, as we know, there are some people who still do have those views.

"It's one of the great strengths of the drama, the script and the whole thinking behind it, that we are able to touch on contemporary issues such as this. I think we all have to do that in the business - to both cast people from different backgrounds and reflect the society in which we all live."

He follows: "It's very much part of the fabric of our lives and it's very important we acknowledge that in popular television."

Where would he place this show in relation to the influx of other, somewhat grittier crime dramas on our TV screens?

"I've done Line Of Duty and stuff like that and we kind of know what that is, and this is not that," states Watkins, who will feature alongside a roster of guest actors including Robert Lindsay, Susannah Fielding and Joanna Scanlan.

"It's unashamedly different. It has that sort of puzzle thing to it, the solve-a-crime thing, which we find satisfying. So it obviously deals with murder, but it's done with a great sense of humour, in a format that we know.

"Yet it's interesting that terrestrial television still occupies almost half the viewing population," he muses. "So, despite streaming, Netflix and all those other platforms, people still want to watch something on a Sunday night!

"Some people don't want to watch those gritty ones because they're too hard to watch - I love them - so this is a gentler way in."

Next, Watkins will play biographer Brian Masters in ITV drama Des, a three-part commission that follows the arrest and trial of serial Killer Dennis Nilsen (helmed by David Tennant).

However, looking to the future, Watkins quite fancies doing "something in the States" - along the same lines as long-running hit TV series such as Fargo and Mad Men, he says.

"That would be really exciting as it's different world!" he quips. "It's great stuff that's coming my way, now - The Crown is opening doors," he confides.

"I think you've got to decide that that's what you want to do and you have to go and get it, but it's difficult when you've got family at home. It's a big commitment," he concludes.

"What I'm hoping is that, because of The Crown - I've not necessarily become a brilliantly better actor, it's just that one's profile has increased - that my chances are slightly higher."

McDonald & Dodds, STV tomorrow