James Corden's announcement that he is stepping down as host of The Late Late Show has created waves in the US, where talk shows are big business.
For eight years, the Buckinghamshire-born entertainer has held his own against some slick US competition and "truly reimagined many elements of the late night format", as the boss of the CBS network put it.
The Late Show with Stephen Colbert may have reigned in the ratings for the past five years, but entertainment website Deadline said "Corden's show has been built for a viral age".
The Late Late Show's YouTube page has had almost 10 billion views, Deadline added, and has more than 27 million subscribers - second only to Jimmy Fallon on 29 million.
When Corden took over hosting duties from Craig Ferguson in 2015, he was an award-winning actor and writer.
He had co-written and starred in Bafta-winning BBC sitcom Gavin and Stacey, and led the cast of West End play One Man, Two Guvnors. When that show transferred to Broadway in 2012, it earned Corden a Tony Award and made his name in the US.
As well as offering laughs and chat, Corden brought shareable sketches along for the late-night ride - notably Carpool Karaoke, in which he drove around with hugely famous celebrities while singing to their biggest hits.
It may sound simple, but the Wall Street Journal's Jason Gay called it a "cultural phenomenon" and a "seismic breakthrough" for Corden's show.
The idea started when Corden was on the BBC's Comic Relief fundraiser in 2011, with George Michael in the passenger seat.
Corden later told the Mail on Sunday: "It wouldn't exist without him and his ability to laugh at himself. No question."
A year after he started his talk show, Corden's YouTube channel was already reaping the rewards. Carpool Karaoke outings with Adele, Justin Bieber, One Direction and Michelle Obama helped him surpass a billion total views,
The former US first lady sang along to hits by Beyonce, Stevie Wonder and Missy Elliot, who also made a surprise appearance. "It's official: we, the people, have the most viral First Lady ever," wrote Vanity Fair.
The First Lady may have gone viral, but it was Corden's vehicle all the way.
In 2016, the Wall Street Journal said Carpool Karaoke had become "one of the most successful YouTube franchises of all time", and its views were "approaching Super Bowl numbers".
Corden also drove around Liverpool with Sir Paul McCartney for a Carpool Karaoke special.
David Taylor, group managing partner of The Brandgym, said Corden had used social media to "ignite" content for his nightly TV show.
"What James Corden has done incredibly well is to leverage this TV content, and amplify it with social media to create fame," he said.
Corden's departure from his TV juggernaut is not a total surprise - he hinted a couple of years ago that he and his family were homesick.
"Ending the show will always be a bigger family decision than a professional one," he told The Sun in 2020, adding: "I have an overwhelming feeling that our family has walked to the beat of my drum for a very long time."
'A good run'
Los Angeles Times entertainment reporter Anousha Sakoui told BBC Radio 5 Live on Friday: "It's a very competitive space for late-night talk show hosts. So, you know, he's had a good run."
But Corden's "good run" has not been without problems - which have also played out on social media.
Corden "did invigorate the show from when he took over", Sakoui said, adding: "He managed to get Prince Harry and Megan on at a time when people were desperate to find out more about them."
However, Sakoui said he had faced controversy on his own show while appearances in films like 2019's live-action remake of Cats "divided opinion quite viciously".
She explained: "I think he split Americans to some degree. He was popular with some, but not popular with others."
In 2019, there was what the Hollywood Reporter described as an "embarrassing reminder of his unpopularity" when Corden and the Carpool Karaoke team agreed to do an Ask Me Anything Q&A on Reddit. The session only lasted for three questions after Corden was deluged with more than 700 negative comments.
Last year, the host faced criticism for a section on his show called Spill Your Guts or Fill Your Gut, which was accused of mocking traditional Asian food.
Another one of Corden's show segments, Crosswalk the Musical, was said to have annoyed commuters and social media users when he and fellow stars of last year's live-action Cinderella film performed numbers in the street.
"Corden, dressed as a rat, can be seen thrusting his groin at the car while singing the chorus to Jennifer Lopez's Let's Get Loud," the Hollywood Reporter said, adding: "The reaction on Twitter has been overwhelmingly negative and reignited a debate about the multihyphenate's popularity."
Beyond his own show, his casting and performance as a gay Broadway actor in Netflix's 2020 musical The Prom attracted criticism for being stereotypical and homophobic.
Corden did manage to have the last laugh about Cats. He and fellow co-star Rebel Wilson mocked the film's special effects at the 2020 Oscars, and he said afterwards he was "happy to poke fun at himself".
Richard Bean, the writer of One Man Two Guvnors, acknowledged that his former leading man can divide opinion, telling BBC Radio 4's Today programme he is "a bit Marmite nowadays", referring to the foodstuff that people famously either love or hate.
But Bean described Corden as "incredibly hardworking, ambitious, amazingly professional, with comic timing on stage to absolutely kill for".
So what next for the star? It sounds like he will return to the UK, or at least spend a lot more time there.
Sakoui said it could be a "difficult transition".
"These presenters get a lot of money, big contracts, and it's a huge audience, compared to what you might get in the UK," she said.
She wondered if Carpool Karaoke "might end up spinning out into something standalone" starring Corden because "there's some really popular segments of the show I think people would miss".
Bean was delighted at the thought that Corden might be returning home. "It's great. If we can work together again it would be be fantastic. It's really great news for Great Britain," he said.
Chat host rival Stephen Colbert even suggested Corden could be the next star of long-running BBC series Doctor Who.
.@JKCorden Congratulations, James, on what will be eight incredible years at CBS. 12:30 won’t be the same without you. But looking forward to your exciting adventures as the new Doctor Who! pic.twitter.com/MGW0J9t0qe— Stephen Colbert (@StephenAtHome) April 28, 2022
"It ends so open I think it would be a shame to leave it there," Corden told BBC Radio 2's Zoe Ball last year.
He will no doubt not be short of offers - but hasn't been drawn on his plans just yet.
Announcing his departure from his show, he said: "I never saw as it as my final destination, and I never want this show to overstay its welcome.
"I love making it and I really think in a year from now that will be a good time to move on and see what's out there."