WATCH: An ‘All I Want For Christmas Is You’ Carpool Karaoke With Every Celeb Ever Exists

The best Christmas song this world has ever seen has just been Carpool Karaoke'd.

A surprise Christmas version of the iconic bit hit screens last night leaving us reeling as the greatest seasonal reveal TV as ever seen happened without us even being a little bit aware. 

Mariah makes a seasonal return along with Adele, Lady Gaga, Selena Gomez, Elton John, Demi Lovato, Nick Jonas, the Red Hot Chilli Peppers, Gwen Stefani, Chris Martin and MORE. 

It's a hoot.

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