It's time: Watch Mariah Carey pull an insanely festive prank on Jimmy Kimmel while he's sleeping

Mariah Carey ambushed a sleeping Jimmy Kimmel to remind him that it's tiiiiiiiiiime!

The diva pulled a festive prank on the late-night host this week, showing up to his bedroom at 2 a.m. when he was deep in slumber, mouth guard firmly planted, to drown him in Christmas paraphernalia and let him know that he should officially begin to prep for her favorite holiday. As her hit song "All I Want For Christmas Is You" blasted in the darkened bedroom, dancers sprinkled fake snow on Kimmel's bed.

"Come on! We bathed together," Carey said, referencing a 2016 Jimmy Kimmel Live segment in which the host interviewed the singer in a tub. "This is the next step."

Later, a groggy Kimmel made his way downstairs in his wife's robe, where the Queen of Christmas presented him with a T-shirt with her face on it that read, "It's time!"

Carey appeared on Thursday's episode of Kimmel's late-night show after the prank, discussing her penchant for making crank calls and marveling at the continued success of "All I Want For Christmas Is You," which dominates music charts every December.

"It's the first Christmas song I ever wrote, and I never was like, 'These type of results are going to happen,'" she said. "I just wanted it to sound like a classic. I just wanted it to be timeless."

The Grammy winner is set to embark on her Merry Christmas One and All tour later this month, bringing merriment and mayhem to 13 cities across the U.S. and Canada.

Watch her ruin a good night's sleep above.

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