THE Oscars have ended with a moment that left everyone speechless - but not in a way anyone expected.
Accounting firm Pricewaterhouse Cooper later took responsibility for the blunder.
The La La Land filmmakers were part way through their speeches when the real winner of the Oscar, Moonlight, was announced.
Kimmel said: "This is very unfortunate what happened. Personally I blame Steve Harvey for this - I would like to see you get an Oscar anyway. Why can't we just give a whole bunch of them."
Steve Harvey famously announced the wrong Miss Universe winner in 2015. Moonlight director Moonlight director Barry Jenkins looked gobsmacked at his swing in fortunes.
Pricewaterhouse Coopers, which counts votes and provides envelopes for the Oscars, apologised for the mix-up.
"We sincerely apologise to Moonlight, La La Land, Warren Beaty, Faye Dunaway, and Oscars viewers for the error that was made during the award announcement for Best Picture," a statement from the company read.
"The presenters had mistakenly been given the wrong category envelope and when discovered, was immediately corrected.
"We are currently investigating how this could have happened and deeply regret that this occurred. We appreciate the grace with which the nominees, the Academy, ABC and Jimmy Kimmel handled the situation."
La La Land's producers gracefully handed over their Oscars - "I'm going to be proud to hand this to my friends at Moonlight," said Jordan Horowitz - and held up the correct envelope proclaiming Moonlight the Best Picture winner.
Amid mass confusion - and host Jimmy Kimmel assuring everyone it wasn't a joke - Warren Beatty, who had announced La La Land as the winner, returned to the mic to explain the stuff up.
"I want to tell you what happened," Beatty said. "I opened the envelope and it said, 'Emma Stone, La La Land' - that's why I took such a long look. I wasn't trying to be funny. This is Moonlight, the Best Picture."
The LA Times quoted Australian actress Nicole Kidman as saying: "I'm in shock. That was the craziest thing I've ever seen."
"It's very humbling to be up here and I hope even more than that it's inspiring to little black boys and brown girls and other folks watching at home who feel marginalised and can take some inspiration from seeing this beautiful group of artists, helmed by this amazing Barry Jenkins, up on stage collecting this top honour," said Romanski.
Kimmel captured the bamboozled tone as he wrapped up the Academy Awards ceremony and telecast.
"I don't know what happened - I blame myself for this," the host said. "Let's remember it's just an awards show. We hate to see people disappointed but the good news is that we got to see some extra speeches ... We had some great movies.
"I knew I would screw this show up, I really did. Thank you for watching."
During her winners' interview backstage afterwards, a wide-eyed Emma Stone - who had been up on stage with the La La Land team as they accepted their Best Picture "win" - declared: "Whoo! You guys see that?!"
Asked her reaction to the mix-up, she certainly didn't sound disappointed the Moonlight actually took the top prize.
"I f---ing love Moonlight," Stone said.
"God I love Moonlight so much. I'm so excited for Moonlight. Of course it was an amazing thing to hear La La Land - I think we all would have loved to win Best Picture - but we are so excited for Moonlight. I think it's one of the best films of all time, so I was pretty beside myself."
Without naming names, she questioned Beatty's "wrong envelope" explanation.
"I was also holding my Best Actress in a Leading Role card that entire time," Stone said, "so whatever story - I don't mean to start stuff - but whatever story that was, I had that card."
Soon after the gaffe, social media users went crazy with their Oscar memes.
Later in the evening, La La Land producer Horowitz told the Hollywood Reporter's Scott Feinberg: "I got to thank my wife and kids ... to accept an Oscar ... and to present an Oscar - all within 10 minutes."
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