Sorry, but this is really, really great! Jon Hamm was the first celeb to stop by Vanity Fair's studio at Sundance this year to lay down some lyrics to the hit Justin Bieber song "Sorry," and he had to admit the tune wasn't one on his usual playlist!

"Is it too late to say I'm sorry that I don't know the song 'I'm Sorry' by Justin Bieber?" the Mad Men star says to the screen.

But Hamm needn't have worried, as it turned out there were 28 other celebs at the ready to lend their voices to Bieber's lyrics, and some really big names got involved!

Nick Jonas, John Legend, John Krasinski, Don Cheadle, Chelsea Handler, Ellen Page and Chloe Sevigny were just a few of the stars who happily uttered the 21-year-old pop star's poignant lyrics  and the results are extremely dramatic!

According to Vanity Fair, the production was an homage to W Magazine's celeb-filled rendition of Drake's Hotline Bling.

Watch the hilarious video above, complete with furrowed brows, teary eyes and even a total emotional breakdown finale!

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