Thankfully, when he pitched the idea to Mimi, she “got it”, and history was made… although there were still a few bumps in the road (pun intended) to smooth out along the way.

“She came out and said, ‘Oh, I'm not singing today,’ and she went, ‘We'll just drive around and have a chat,’” recalled Corden.

“I went, ‘Oh, right. It's just, we call it Carpool Karaoke, so without that...’And then I thought, I've just gotta go. I've just gotta jump into it. Even if this bit is just me singing to Mariah Carey, it's still on the show. It may not be the recurring bit that we hope it is, but it's still probably on the show.”

James Corden unveils surprise star-studded Christmas Carpool Karaoke