Eminem's Surprise Oscars Performance of 'Lose Yourself' Shocks Celebs and Fans

The 47-year-old rapper decided to show up to the Oscars after all -- 17 years later.

Surprise! Eminem finally had his Oscar moment... 17 years later?

The 47-year-old rapper took the stage on Sunday in an unannounced performance of his Oscar-winning song from 8 Mile, "Lose Yourself," and the surprise musical moment was unexpected and was received with mixed reactions from the star-studded audience. (ET spoke with ABC executive Robert Mills on Monday about how the Oscars pulled off the surprise performance.)

After Lin-Manuel Miranda introduced a lengthy montage featuring iconic movie moments with famous songs, which ended with Eminem's "Lose Yourself," the rapper and his band suddenly appeared from below the stage in a shocking reveal. And the signature notes suddenly echoed throughout the Dolby Theatre as he went into a full performance of his song. 

Eminem took to Twitter immediately after his performance to address his surprise Oscars appearance, tweeting, "Look, if you had another shot, another opportunity... Thanks for having me @TheAcademy. Sorry it took me 18 years to get here."

While several famous Oscar attendees were unsure of how to react, there were some who were all-in on Eminem's mini-concert and others who were less interested in jamming out to a rap song on Hollywood's biggest night.

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Gal Gadot, Kelly Marie Tran and In the Heights star Anthony Ramos were among the celebrities who were rockin' to the beat, but Martin Scorsese, Idina Menzel and Bille Eilish and her brother, Finneas O'Connell, looked a little more than confused as to why Eminem was even there in the first place. (As was Twitter.) Brie Larson looked like she was consumed with multiple emotions, including shock and awe. 

After Eminem's performance, the Dolby crowded erupted with a standing ovation.

So, why was Eminem even at the Oscars on Sunday? Fair question.

It may be easy to forget that Eminem is an Oscar winner, taking home the Original Song statuette in 2003 for "Lose Yourself," which was featured in the semi-autobiographical film, 8 Mile. The rapper didn't attend the Academy Awards that year because he preferred to stay home in Detroit, Michigan, and reportedly napped through his Oscar-night upset.  

That year, Eminem beat out Renee Zellweger and Catherine Zeta-Jones' "I Move On," from Chicago; Caetano Veloso and Lila Downs' "Burn It Blue," from Frida; U2's "The Hands That Built America," from Gangs of New York; and Paul Simon's "Father and Daughter," from The Wild Thornberrys Movie.

Eminem has been out and about the past several months, showing support for his fellow friends (like at 50 Cent's Walk of Fame ceremony) and being more visible in the public eye after releasing his latest album, Music to Be Murdered By..., in January.

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