By Sandra Gonzalez

CNN

(CNN) -- Director Barry Jenkins said he "speechless" after his movie "Moonlight" was announced as the winner of best picture on Sunday night, following an unprecedented moment in Oscars history. And he wasn't the only one.

"Is that the craziest Oscar moment of all time?" Emma Stone asked backstage. "We made history tonight."

But what exactly happened that led to that now-infamous moment where "La La Land" was mistakenly announced as best picture at the Academy Awards?

Here's how it all went down:

Faye Dunaway and Warren Beatty present

Faye Dunaway and Warren Beatty -- on hand to celebrate the 50th anniversary of "Bonnie and Clyde" -- presented the nominees for best picture. On stage, Beatty was given the task of opening the envelop that was supposed to contain the winner. (Later, Beatty would say it contained the name of a winner, but not the winner.)

On stage, Beatty looked at the card and said, "And the Academy Award..."

The crowd laughed, assuming he was building suspense.

He looked down at the card again and then looked at Dunaway.

"...for best picture..."

Dunaway playfully told Beatty, "You're awful." She assumed he was joking around.

"Come on," she prompted him.

He showed her the card, and Dunaway read it aloud.

"'La La Land,'" she said.

'La La Land' has a lovely night...briefly

"La La Land" producer Jordan Horowitz was the first to speak. Producer Marc Platt followed.

As Platt spoke, viewers at home saw someone run across the stage behind him.

From the crowd, "Moonlight" actor Mahershala Ali, a winner for best supporting actress, noticed the activity.

"When I did see security or people coming out on stage, and their moment was being disrupted in some way, I got really worried," he told press backstage.

Jenkins wasn't surprised by the initial result.

"I think all the movies that were nominated were worthy so I took the result," he said backstage. "I applauded like everyone else."

On stage, "La La Land" producers were approached by a man wearing a headset and holding an envelope.

Platt called producer Fred Berger to the mic next. As Berger began speaking, Beatty started heading to the mic, but Berger beat him to the announcement.

"We lost, by the way, but, you know," he said.

Horowitz clarified: "I'm sorry, there's a mistake. 'Moonlight,' you guys won best picture."

"This is not a joke," he said, gesturing to the "Moonlight" cast and producers and inviting them to stage.

Platt added: "This is not a joke. They read the wrong thing."

Horowitz showed the envelope to the crowd.

"I wanted to express to them that they had won," he told CNN later.

'Moonlight' wins

Jimmy Kimmel then hopped on stage and attempted to clear the air.

"I think you all should just keep it anyway," he joked.

Off stage, the "Moonlight" crew celebrated. Director Barry Jenkins covered his mouth in shock.

"It threw me more than a bit," Ali said. "I didn't want to go up there and take anything from somebody. It's very hard to feel joy in a moment like that."

As the "Moonlight" cast and creators headed to the stage, Kimmel said, "This is very unfortunate what happened."

"Personally, I blame Steve Harvey for this," Kimmel said, referring to the TV host's infamous Miss Universe gaffe.

"I'm going to be very proud to hand this to my friends from 'Moonlight,'" Horowitz interjected.

Beatty attempted to explain himself further.

"I want to tell you what happened. I opened the envelope and it said, 'Emma Stone, La La Land.' That's why I took such a long look at Faye and at [the audience]. I wasn't trying to be funny."

Stone later told press she was confused because she had the card that said her name with her "the entire time."

According to The Hollywood Reporter, the accountants from PricewaterhouseCoopers (PwC) typically create two complete sets of winners' envelopes. So it is possible Stone had her envelope and another was handed to Beatty.

"During the ceremony, two accountants stand on opposite sides of the stage throughout the ceremony, alternating between each other in the handing out of envelopes, depending on which side of the stage the presenters enter from," according to THR.

Behind Beatty, the two casts traded spots.

"This is 'Moonlight,' the best picture," Beatty said.

Matt Damon whistled from the crowd.

Taraji P. Henson was shown with her mouth wide open in the crowd.

"Very clearly, even in my dreams this could not be true," Jenkins said. "But to hell with dreams. I'm done with it because this is true."

Jenkins also offered a thanks to the "La La Land" team.

"I have to say, and it is true, it's not fake: We've been on the road with these guys for so long. And that was so gracious and so generous of them," he said. "My love to 'La La Land.'"

"Moonlight" producer Adele Romanski summed up: "Thank you to the Academy. I don't know what to say. I'm still not sure this is real."

The aftermath

Emma Stone was the first directly involved in the viral moment to address the press backstage.

"I don't even know what to say," she said. "I think it's an incredible outcome, but very -- a very strange happening for Oscar history."

She also expressed her love for "Moonlight."

"God, I love 'Moonlight' so much. I was so excited for 'Moonlight," she said.

Jenkins, meanwhile, said he was given no official explanation for what happened.

"I will say, I saw two cards," he said. "I wanted to see the card...and [Beatty] refused to show the card to anybody before he showed it to me. And so he did. He came up stairs and he walked over to me he showed the card....and I felt better about what happened."

Jenkins thanked the "La La Land" team for being "so gracious" in the moment.

"I can't imagine being in their position and having to do that," he said. "We spent a lot of time together in the last six months and I can't imagine being in their position and having to do that. It's wild."

He added: "I wasn't speechless because we won. I was speechless because it was so gracious for them to do that."

CNN's request for comment from the Academy and was not immediately returned.

PwC said in a statement: "We sincerely apologize to 'Moonlight,' 'La La Land,' Warren Beatty, Faye Dunaway, and Oscar viewers for the error that was made during the award announcement for Best Picture."

"The presenters had mistakenly been given the wrong category envelope and when discovered, was immediately corrected," the company said. "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," the statement added."

CNN's Stephanie Elam contributed to this report.