Keeley Bolger talks to James Corden about his role in new film Into the Woods

He was admittedly going through a bad time during the height of his fame, culminating in a "bratish" turn at the 2008 Baftas, where he used the acceptance speech for Gavin & Stacey winning the Audience Award to question why the show hadn't been nominated for best comedy.

But fast forward a few years, and Corden is a changed man. Married to charity worker Julia Carey and father to three-year-old Max and baby daughter Carey, he has a starring role in Disney's new musical Into The Woods, alongside Meryl Streep, and is replacing Craig Ferguson on the long-running American series The Late Late Show in March.

James in Into the Woods with Lilla Crawford 

Every reason then, to feel a bit smug - but the Corden of today isn't going to play that card. Instead, he is accommodating, cheerful and - whisper it - resoundingly humble.

As well as his successes, TV triumphs and Tony Award for his role in West End play One Man, Two Guvnors, he has admittedly had his failures too.

"My experience of 'having a moment' is that they're very quickly followed by sharp twists into unpleasant times," explains the 36-year-old.

There's been the poorly received Horne And Corden sketch show with his Gavin And Stacey co-star Mathew Horne, followed by their film flop Lesbian Vampire Killers, and an altercation with Patrick Stewart (who provoked the spat by ribbing fun at Corden's belly) at the Glamour Awards.

So although this might be his big moment to break the US, he's been in the fame game long enough to keep a cautious cool about it.

For instance, he is still surprised he landed the sizeable straight man role of Baker in Into The Woods, a Stephen Sondheim musical which blends the lives of famous fairy tale characters into one story, and also stars Emily Blunt, Anna Kendrick and Johnny Depp.

"I thought they'd go and get someone very famous to play my part," explains Corden, who also sang in the recent Keira Knightley musical Begin Again.

But despite thinking a line of Disney executives were going to pressure the director Rob Marshall to find someone better-known internationally, to his "joy and amazement", the role was his.

"I'll always be indebted to Rob for it," says the actor, who is smart in a fitted blue blazer, dark jumper and jeans.

Growing up in Buckinghamshire, Corden loved theatre as a child. In his early 20s, he starred in Alan Bennett's The History Boys, alongside Dominic Cooper and Russell Tovey, and went on to land a role in Teachers and then ITV comedy Fat Friends, where he met his future Gavin & Stacey co-writer Ruth Jones.

Presenting "juggernaut of a TV show" The Late Late Show was never part of his plan, but it's a move he's chuffed about, not least because it gives his family life a "consistency", which is hard to find with hectic film and theatre schedules.

"Here's a job where someone is saying you can really be around and be a present father and husband," says the actor, who'll live in California with his young family.

"That's incredibly precious. All your children want is for you to be around. They really don't care what car you drive or what house you live in, or anything like that, they just want you to be around, and I'm thrilled that until the show gets cancelled, I will be able to."

James with his wife Julia 

He's up for the challenge of presenting the talk show, but admits he's not entirely sure how things will work out.

"It feels like someone came and tapped me on the shoulder and went, 'Well done, you've joined Sky's Tour De France team'," he says, grinning. "And before you know it, you're on a bike in Lycra going, 'You know I don't do this guys?'

"I do feel a little like that, but it's going to be a real adventure. I don't know anyone on their death bed who says, 'I wish I hadn't lived in that other country for a little while'."

When he's considering work, it sounds like the worst case scenario is always on his mind.

"Well, I think it's important to 'Google Earth' yourself from time to time, and see how irrelevant a lot of it is," replies Corden, who is also in the early stages of writing a new TV script.

"That makes me feel a bit better. It makes me go, 'That's a pretty high-class problem, if your late night show on CBS gets cancelled...'

"It's not a big a deal really, it's just my career. The things that are actually going to shake me and hit me are things I will never ever be able to control. It'll be the 3am phone call one day when something has actually happened."

Looking back now, Corden's career has "surpassed any expectations" he had for himself.

"When I was 17 and I was in [theatre show] Martin Guerre, it was my first ever job. I was at the back of the chorus and I thought, 'Oh my god, I've just done it. I've made it. I'm doing it'," he recalls.

"If somebody had told that kid that I'd write a sitcom that would be so beloved, and another one which is so well received, and be in plays, including two original productions at the National Theatre which will probably be performed long after we all die... what more can I really wish and hope for?"

And far from being "pessimistic", he says the more he can "prepare" himself if things don't take off, the "happier and healthier" he will be.

"I'm going to give it my absolute best and give it everything I've got to try and make a show that will make America smile before, or more likely, while they fall asleep," he says.

"But I'm under no illusions that it will be anything other than a disaster, because what are the chances? I'm 16st, from High Wycombe and I've never really been on American network TV before, so it couldn't feel more random.

"But I'm going to enjoy the ride. I'm determined to enjoy it."

EXTRA TIME - FIVE BRITS ON AMERICAN TALK SHOWS

Sir David Frost, The David Frost Show (1969-1972) - The legendary late journalist's high profile interviews on his American chat show, including his take down of Henry Kissinger, were so riveting that they're still talked about today.

Sharon Osbourne, The Sharon Osbourne Show (2003-2004) - At the height of the Osbournes' fame, matriarch Sharon presented her own chat show, often calling upon her own family to pop up on the sofa.

Craig Ferguson, The Late Late Show (2005-2014) - The Glaswegian-born presenter has stepped down after a successful decade-long run, and is rumoured to be hosting a new early evening American chat show.

Alexa Chung, It's On With Alexa Chung (2009) - The model-turned-presenter hosted her daily talk show on youth network MTV.

Piers Morgan, Piers Morgan Live (2014) - The former Britain's Got Talent judge and newspaper editor tried his hand at hosting a daily news and talk show, but it came to a halt after six months on air.

Into The Woods is in cinemas everywhere now.