Broadchurch: Jodie Whittaker and Andrew Buchan on the chemistry that made the show so compelling

Whittaker was just one of a thousand reasons why Broadchurch, which sprang into that endless-winter-never-spring of 2013, stapled us all to our sofas. Nothing about it looked like a classic British murder story. There was little artifice to the central couple: “You don’t look at Andy and me and think, ‘They’re a bit Hollywood-looking.’ We’re not Hollywood-looking, we look like people who live in that place.”

At the same time, there was nothing depressing about the look of the series. “Usually, grim stories are told with grim backgrounds,” Whittaker continues. “The colours are ashen, greys and blues, it’s urban, it’s cold... But in this, everything clashed, the costumes clashed, the backdrop of summer, that exquisite beach... And then the worst thing happens.”

Andrew Buchan, meanwhile, was a portrait of devastation, so it is equally surprising – despite loads of previous incarnations, swashbuckling in The Fixer, rugged in the Cranford Christmas special – to see him so chic and cheerful. He doesn’t really think of himself as popular, certainly not as a “Face”. He swears he never gets recognised unless he deliberately goes out dressed up as one of his characters.

Describing his career just after he left Durham University, where he studied modern languages, he says: “My apprenticeship was in places like the Edinburgh Festival with stuff dripping on you. I was always, like, ‘I want to be in grimy coffee shops without a penny to my name.’ I didn’t have any master plan, no.”

Whittaker couldn’t be more different: “I always knew I wanted to act. But I also knew that at 18 I had absolutely no desire to go to drama school. So at 14, I started saving: I was going backpacking at 18. At 18, I knew I was going to drama school at 20. At 20, I was going to graduate and work at 23. And I’m a jammy little b*****d, because all of those things played out.”

There’s no smugness to her, and she’s not looking for admiration. “When I was travelling, I kept getting these emails going, ‘Your mum and dad have told us what you’re doing, we’re so proud of you.’ And I’d be lying on a beach, drinking a beer, hungover from three days’ drinking, thinking, ‘How is this anything to be proud of?’ I just got a bit fatter. I came back a little pudding.” There is a really fresh, wind-blasting vim to her.

Hearing Buchan’s relaxed self-deprecation against Whittaker’s sleeves-rolled-up energy, I can’t help thinking they’d make a perfect real-life couple. But that may just be the huge shadow cast by the show. In reality he’s married to Amy Nuttall (Ethel in Downton Abbey), and Whittaker to American actor Christian Contreras.

She waits until Buchan’s out of earshot to say, “Of anyone I’ve worked with, Andrew is by far the most extraordinary. He has something that (a) you can’t teach, and (b) is not about him. He does a different thing in every take – not trying to be tricksy, just because he responds absolutely to what you do. He’s got that masculine anger, as well as a face full of snot and tears that haven’t taken him 55 minutes to drum up. To have someone you think is ace and love hanging out with is just amazing. Our characters weren’t nice to each other at all. But because we got on in real life, you believed we’d been together for 15 years.”

As a general rule, things that work on screen also worked in the making of them, being the product of people who understand one another. Buchan recalls, “Despite the fact that we’re basically spending seven and a half hours [on screen] grieving, a lot of the cast were exceptionally witty. It was great to have that craic.”

Whittaker adds, “It was one of the most ensemble things I’ve done. I mean, David Tennant and Olivia Colman led it...” Buchan cuts in, “They didn’t lead it that well, though, did they? We were the leaders really...” Whittaker ignores him. “David and Olivia are the funniest, loveliest, most hard-working people. It was like a big family.” Serious for a second, her co-star ensures the writer, Chris Chibnall, isn’t airbrushed. “It’s a credit to the writer as well. Each scene seemed to get harder, but it was always different. The grief always took a different shape, the numbness, the anger.”

“You’ve got eight hours, sometimes you’re going to like the characters, sometimes not,” she adds. She turns to Buchan. “Apart from you. Nobody liked you. You cheated on me.”

I wonder if not being a parent made playing the grief easier? Neither has children. “I think it’s irrelevant, honestly,” says Whittaker. “You know what love is, you know what loss is. I think we would have played it the same. We’ve all got nieces or nephews or best friends’ children, there’s someone you love and can’t imagine loving more.”

Next, he’ll be in ITV’s Great Fire of London as a 17th-century baker (and coincidentally she recently starred in The Smoke on Sky1). There’s to be a second series of Broadchurch, but nobody in the world will say who’s in it. If you’ve got used to this pair married, you’ll have to get unused to it. But if you’re relying on them, separately or together, to stay right at the centre of your home-drama schedule, you’ll be just fine.

Broadchurch has been nominated for the Bafta Radio Times Audience Award.

It’s up to you to decide the Radio Times Audience Award from the six TV shows shortlisted (Breaking Bad, Broadchurch, Doctor Who: The Day of the Doctor, Educating Yorkshire, Gogglebox, The Great British Bake Off). Voting closes 12 noon, 15 May. The British Academy Television Awards are held on 18 May. Vote online at radiotimes.com/bafta.

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