James Corden was on top of the world at the height of Gavin & Stacey's popularity - but his behaviour started to spiral out of control. The funnyman, who is back in the headlines after being banned from a top New York City due to his treatment of waiting staff, has previously spoken about his unacceptable treatment of other people.
At James' lowest ebb, he confessed he was being "rude" to his closest friends and colleagues, including best pal and Gavin & Stacey co-creator Ruth Jones. The pair first met while starring on ITV drama Fat Friends in 2000 - and worked together to write the script for their own sitcom.
They first pitched the idea of a long distance couple who met after speaking on the phone as a one-off pay, but the BBC asked for a series.
James and Ruth became household names playing Smithy and Nessa as well as writing the show - and awards soon followed.
It should have been an amazing night of celebrations when Gavin & Stacey won Television Programme of the Year at the 2008 TV Baftas.
But James wasn't happy and used his acceptance speech to moan that the series hadn't also been nominated for Best Sitcom.
"Instead of applause, I was met with silence, shock and disbelief," he wrote in his 2011 autobiography.
"Now, of course, I can see why and how it must have looked – ungracious, ungrateful and brattish. Rather than using my speech to thank everyone who'd helped on the show, I'd ruined the moment and belittled myself in the process."
It was the start of a bad time for James, whose behaviour got worse and he even started being rude to Ruth.
"As 2008 wore on, it got so bad I was being rude to my agent and I even started being rude to Ruth. If I was in company and the conversation wasn't revolving around me, I would just switch off," he said.
James' career had skyrocketed, as he fronted comedy sketch show Horne & Corden with Gavin & Stacey actor Matthew Horne and they both starred in their own horror-comedy movie, Lesbian Vampire Killers.
He was even asked to host the Brit Awards alongside Kyle Minogue, but the comedian admitted it was "the unhappiest he had ever been".
His sketch show and film were panned by critics and disliked by audiences - and the failed projects were part of the reason that James and Matt started to drift apart until they no longer spoke.
In his autobiography, James added: "We had gone from heroes to zeroes. It hurt. I knew I was to blame. The person I had become wasn't the person I had wanted to be. I had drifted so far from my close friends and family that I didn't know how to pick up the phone and talk to them any more."
Thankfully, James took some time out to re-evaluate his life and managed to turn things around by starring in stage play One Man, Two Guvnors.
When the play went to Broadway he won the Tony Award for Best Actor, which led to him being cast in 2014 Into The Woods, before he was chosen to host The Late Late Show.
James has also stayed close pals with Ruth, who recently said they would "always be friends" because they shared the "life-changing experience" of the hit TV show becoming a success.
Speaking to Good Housekeeping, she said: "We’ll always be friends because we shared this life-changing experience. Neither of our careers would be what they are if it wasn’t for Gavin & Stacey and we’re both incredibly grateful for that.
"It's funny because it’s 15 years since the first episode. And so much has happened since then, yet it feels like yesterday."
While their characters have romantic links on-screen, Ruth is married to husband David Pete, while James is with wife Julia Carey.
The pair may argue from time to time, but they feel like they are as close as family members.
Speaking in 2019, Ruth said: "The journey that we've been on, we can argue don't get me wrong, we have very brotherly sisterly relationship but our friendship at the heart of it is so strong and I am so proud of our friendship and I'm proud of the journey that we've been on together."
And Ruth hopes to see more of her friend when he returns to the UK after seven years as host of The Late Late Show.
"We are friends more than writing partners," she told the Independent last month. "So, it will just be really nice to see more of him. Because I haven't seen him now for over a year."
Rob Brydon, who also starred in Gavin & Stacey with the pair, once opened up on the time where he confronted James about his changing behaviour.
The Uncle Bryn actor, who hosts Would I Lie To You, said he took James out for lunch to have a word with the star about his antics.
"I'd known him for a while – we met on a big comedy-drama called Cruise of the Gods in about 2002," explained Rob.
"I was very impressed by him, although he was very young, very green – very provincial is how I would describe him, not unlike myself at that age. He is such a talent, James, good God he really is. So he was on a rollercoaster."
Despite admiring his co-star, Rob added: "He was burning the candle at both ends, and becoming ratty and irritable."
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