The actor and presenter, who's had to scale back his show once again by hosting from his home due to the pandemic, could be seen in a white pantsuit complete with wig and glasses to boot, leaving fans to flood to the comments to express their delight at his get-up.
WATCH: James Corden transforms into Diane Keaton for Late Late Show segment
One person commented underneath the video: "I genuinely thought he was John Lennon or Liam Gallagher lmao." A second person joked: "James... Papa Mochi... are, are you okay? Do you need Hobi water? I- I- worry sometimes." While a third simply wrote: "Hahaha yes!" complete with a string of crying-with-laughter emojis.
The funny segment was to celebrate the Academy Award winner's birthday as James told the viewers: "Today is a very special day and most auspicious day, it's a day of wonder, a day of excitement, a day of fedoras, celebration and yet more fedoras.
"Today, of course, we celebrate the birthday of our favourite fashion icon. I am talking about, of course, the one, the only Diane Keaton."
James is hosting the Late Late Show from home
He continued: "This year, being her 75th birthday, we have pulled out all the stops. Unfortunately we've had to scale back the event, none of us are together but we still wanted to celebrate. It seemed only fitting that we honour this pant-suit goddess by hosting our very own Dress like your favourite Diane Keaton challenge."
James has had to once again move into his garage at his home in LA to film his nightly chat show due to the growing numbers of positive coronavirus cases in America. The Gavin and Stacey star even opened up about his life in lockdown on the Duke and Duchess of Sussex's new podcast Archewell Audio, stating he was recording from the "spare bedroom in my house".
He added: "I think being able to spend time with my children, I feel like my relationship with them has changed. Being around them more, the five of us in our house has really brought quite a lot of joy to me."
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