It was one of the most shocking moments in Oscars history: after announcing La La Land as the best picture winner at Sunday’s ceremony, one of that film’s producers returned to the microphone and said there had been a mistake: Moonlight was the actual winner of the night’s top prize.

How did this happen? Here’s a closer look at the lead-up to the mix-up — and the ensuing fallout.

Error in Judgment

It may have started with a tweet… but it ended with a gasp. The Oscar telecast was going well until PricewaterhouseCoopers accountant Brian Cullinan handed best picture presenter Warren Beatty the wrong envelope. One of only two people on the planet who knew the winners in advance, Cullinan was parked on the left side of the stage while his Oscars colleague, Martha Ruiz, was stationed on the right. Each had an identical set of sealed envelopes to hand to the presenters before they waltzed into the spotlight.

According to PwC, each accountant then formed two stacks of envelopes: one for the presenters entering on their side of the stage, and a “backup” stack for those who entered from the other side. Cullinan accidently pulled from the wrong pile, handing Beatty the duplicate Best Actress envelope instead of the one for Best Picture. Why? Reportedly, he may have been distracted, tweeting a photo of best actress winner Emma Stone. (The tweet has now been deleted. PwC did not respond to EW’s interview request.)

Error in Literacy

Beatty, confused by what he saw on the card, stalled while his Bonnie and Clyde costar Faye Dunaway egged him on. “You’re impossible,” she teased. He showed her the card. She called out La La Land.

Panic Button

Immediately, PwC realized the mistake. The two accountants hustled to open the other best picture envelope that read Moonlight before sending a stagehand out to correct the error. La La Land producers Jordan Horowitz and Marc Platt had already given their speeches, and producer Fred Berger was about to begin his when Horowitz saw the correct card. “I took the envelope and went up to the mic,” Horowitz said later at the Governors Ball. “What else 
are you going to do?”

Blame Game

PwC has accepted responsibility, saying in part, “Once the error occurred, protocols for correcting it were not followed through quickly enough by Mr. Cullinan or his partner.” The Academy issued an apology Monday night, but Beatty was in no mood to talk. In an email to the media, he wrote, “Rather than for me to respond to questions from the press about the Academy ceremony, I feel it would be more appropriate for the president of the Academy, Cheryl Boone Isaacs, to publicly clarify what happened as soon as possible.”

Comments have been disabled on this post