WATCH: Tons Of Carpool Karaoke Celebs Record Secret Christmas Song

All I want for Christmas is Lady Gaga, Elton John, Mariah Carey...

Let's face it: James Corden was always going to pull out all the stops for Christmas. It was an inevitability. We could feel it in our bones. It was foretold.

And pull out all the stops he did, bringing Mariah Carey along for a ride to sing her classic, "All I Want For Christmas Is You".

He didn't stop there, either - we lost count of how many celebs popped up to join in. Seriously, have you ever seen Flea so damn happy?

CBS

That's the Christmas spirit for you.

Check out the whole thing below, and try to stop yourself from smiling. You won't be able to.

Feature image: Joern Pollex/Scott Dudelson/Samir Hussein/Gilbert Carrasquillo/Getty Images/CBS

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