Mathew Baynton on The Wrong Mans, Horrible Histories and Yonderland

"It's not Dumb and Dumber. It's closer to Fargo," Baynton tells RadioTimes.com.

"It came out of a conversation James and I were having on set years ago, about those big American box sets that we were all watching: at the time it was 24, Lost and Heroes. We were wondering why nobody attempts that level of story and dramatic ambition with comedy on TV.

"When we started writing it, we realised why people don't do that. It was really hard to write! A lot of man hours just working out plot. Everything has to be taut, moving on at the right pace."

It sounds rather expensive, too. "That's why the BBC hooked us up with [US streaming/catch-up service] Hulu and made it a co-production. We managed to make the show we wrote without any compromise, which is a rare thing to be able to say. It's visually ambitious and we're trying to do something that's thrilling as well as funny. We're proud of it."

The script certainly attracted an impressive supporting cast: Dawn French, Sarah Solemani, Rebecca Front, Emilia Fox, Dan Skinner, Nick Moran, Rufus Jones and, in the trailer, Thick of It stars Vincent Franklin and Paul Higgins. "We just sort of hoped these people would say yes – they all did!"

Baynton and Corden have been brewing the idea for The Wrong Mans for several years: "James and I have been friends since we worked together on a film called Telstar in 2007." Baynton then appeared as Smithy's scene-stealing dimwit friend Deano in series two and three of Gavin & Stacey. "We were friends before Gavin & Stacey became a huge thing – the first series was on but it hadn't become big. I've never worked with him thinking, oh my god I'm working with James Corden the successful comedy writer. I'm just sat in a room with my friend coming up with ideas."

Describing the tone of the show's humour, Baynton says: "We were talking about how the Coen brothers often mine a seam of film noir narratives with unlikely protagonists: Burn after Reading in particular had just come out, with that brilliant Brad Pitt character, a complete buffoon who thinks he's got his hands on something important.

"There are two idiots at the centre of this dramatic, dangerous story. We were trying to put ourselves in their shoes. You think of action clichés you're working towards, like jumping off a bridge onto a moving train. What would have to happen to make you, an ordinary person, make that extraordinary decision? Not acting heroically, but forced into it.

"We always talked about if Jason Bourne got a phone call because there was going to be an assassination attempt on the President and he was the only person who could stop it, but he'd left his phone in the toilet and the cleaner picks it up, what then? That's essentially the premise. Something has to be done, it's just the wrong guy doing it."

Baynton is speaking to RT from the set of Yonderland, which he and his Horrible Histories co-stars - Martha Howe-Douglas, Jim Howick, Simon Farnaby, Laurence Rickard and Ben Willbond – have created for Sky1. Howe-Douglas plays a 33-year-old mum whose kids have just started school. Bored at home, she meets an elf who insists she is "The Special One" in another world, so she steps through a portal and finds, according to Sky, "incompetent knights, monks who are incapable of lying and a race of people intent on firing the cleverest amongst them into the sun". The HH team act with puppets from Baker Coogan, long-time collaborators with the Jim Henson Company.

Yonderland sounds… crazy. "Yeah, it is, quite," Baynton says. "I always liked stuff that snuck surrealism into something quite accessible. That's something Horrible Histories always did quite nicely."

Asked for something to compare Yonderland to, Baynton immediately cites the cult 1986 fantasy film Labyrinth: "That's probably the clearest comparison point, but it's a little bit Booshy in that every week there's an adventure. It's quite quest-y: you're off to find the magic egg or whatever."

And how about acting with puppets? "It's no different to working with actors. You immediately engage with the puppets if the operators are good at their job. If you didn't, it would mean… your imagination has broken. You've grown up too much if you can't have a conversation with a puppet."

Is Yonderland a kids' show? "Our hope is that no-one will feel the need to call it a kids' show. It happens with Horrible Histories: things are a bit more defined than when I was a kid, I suppose because adult comedy in general is a bit more adult than it used to be. It slightly ghettoises family-friendly comedy. With Horrible Histories, it's frustrating now that it's on CBBC, not BBC1. It's more cordoned off.

"We know we have a surprising success on our hands with Horrible Histories and people will inevitably hold us to that standard, and compare Yonderland to it. We just hope they'll go with us and enjoy it for what it is. It's different but similar, in ways you'd hopefully want it to be."

With the fifth and final series of Horrible Histories halfway through its run on CBBC, Baynton's busy year continues in the summer as the HH gang begin work on Bill, their comedy movie about the life of William Shakespeare. That'll be in cinemas in 2014 - Yonderland was originally announced for next year too, but now looks set to land on Sky1 this autumn, at roughly the same time as The Wrong Mans arrives on BBC2.

"I can see it coming: 'Oh, he's everywhere!' But The Wrong Mans would have been made about a year earlier if it weren't for the huge success of One Man, Two Guvnors. We were writing in James's dressing room at the National, then it was in the West End, then Broadway and he won the Tony. It's just the way it works sometimes."

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