Rob Brydon reveals why he initially turned down new BBC series – and what changed his mind

I am genuinely very fond of it and genuinely keen to know more. When [the BBC] first offered me this [three-part series], I declined it because I thought, “I’m no authority on country music”, and it might be perceived as a little opportunistic. But then they came back with the angle of discovering it and I thought, “Well, that entitles me to do it”. Because when some Johnny off the TV like me swans off to make a documentary, I think there has to be a reason for it.

You’re being too modest. You’re actually a country music superstar: your version of Islands in the Stream, with Ruth Jones, got to number one…

That was a novelty record for Comic Relief! I tell my kids, “We were at number one for seven days”. But I do do a bit of singing in this series. Among other things, we go to an Elvis Festival in Franklin, Tennessee, and I meet all these Elvi. I put on my Elvis suit, they announce me, I go out on stage… and it’s blank looks all round. I’m not known over there, so it’s just this short, middle-aged Welshman singing Elvis. I really had to hold my nerve.

This series takes you right round the southern states. What was your general impression?

It’s a whole other country from the rest of the US. Down there, it’s work, play, family and God. We saw a lot of spindly white wooden church steeples, a lot of beautiful disused barns, a lot of lovely open front porches and a lot of food. They’re not on a health kick down there – even the “healthy” options come smothered in a blanket of melted cheese, and the trail mix has M&Ms in it. The people are wonderful though – hugely courteous and very friendly. Take Heidi Parton: she’s Dolly’s niece, and she performs at [her aunt’s theme park] Dollywood. She’s the epitome of southern hospitality – if any holiday-maker goes up and says “Hello”, she’ll stay and chat with them.

There are a few “eccentrics” out there in the backwoods though, no? What about “Big Yeti”?

He was great fun. He’s this huge mountain of a man – I suppose otherwise he’d be called “Small Yeti” – who took me fly-fishing in North Carolina. I didn’t catch anything, but I loved it, standing there in this beautiful river. I finally understood what Paul Whitehouse and Bob Mortimer are banging on about; though I was concerned because it was bear country and we’re stood there looking at the river with our backs to the woods…

If we can’t all tour the American South in its entirety, where should we go for the best music?

Well, Nashville’s “strip”, on Broadway, has to be experienced to be believed. The music bars there go from 10 in the morning until I-don’t-know-when at night. There’s not just a band in each; there’s one on each floor of each bar, and they’re phenomenal. We bumped into Gary Barlow in Nashville; he goes out there for the sheer quality of the songwriters and musicians.

You’re “breaking” America yourself, aren’t you? It was clearly your role as Sugar Daddy Ken in Barbie that made it the 16th highest-grossing film of all time…

I ended up in that because Margot Robbie loves Gavin & Stacey, and knew me from that. I’d actually been asked to record a birthday video message for her, as Bryn, a few years ago, then I sort of forgot about it, because you never know if they really do like the show. For instance, a few years ago someone told me that Johnny Depp loved [Brydon’s 2000 comedy] Human Remains, and I remember thinking, “But does he really?” I’ve never met him, so I don’t know.

Do you think maybe they’re mistaking you for Daniel Craig or someone?

It happens all the time – or maybe Wendy Craig. But now, because of the internet, people can watch your programmes anywhere in the world, so you never know who’s seen it. Our [Gavin & Stacey cast] WhatsApp group still springs into life every so often – and when that Coldplay kiss thing happened [an extra-marital affair between colleagues was accidentally revealed by a crowd-cam at a Coldplay concert], there were all those kiss-cam memes, and Rob Wilfort [who played Jason in G&S] found one of him and me, and sent it to the group.

Finally, which stop on this trip would you most like to go back to?

Rosine, in Kentucky, felt really authentic. It’s talked of as the birthplace of bluegrass, and they have this jamboree there – it’s a bit of a drive to get to Rosine, but it’s so real and you can get so close to it all. I remember thinking all the time that I’d like to come back with my wife Clare, drive around and visit it at a more leisurely rate. I felt that everywhere.

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Rob Brydon's Honky Tonk Road Trip begins Sunday at 9pm on BBC Two and iPlayer.

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