'This is not a joke:' Confusion, Moonlight and other Oscar highlights

There was drama, comedy and even a plot twist on Sunday at the 89th Academy Awards in Los Angeles.

Here are a few memorable moments that stood out and, of course, the one that stood above the rest.

• See the full list of winners from last night's Oscars

The mistake

Best picture presenters Warren Beattyand Faye Dunaway stars of the classic filmBonnie and Clyde were nearly involved in the greatest Hollywood heist of all time when they mistakenly announced thatLa La Landhad won.

While the film's cast and crew were celebrating onstage,La La Landproducer Jordan Horowitz took the microphone and made the correction.

"No, there's a mistake.Moonlight, you guys won best picture" he said. "This is not a joke."

The accounting firm PricewaterhouseCoopers, has handled Oscar balloting for decades. PwC sent out a statement apologizing for the error, saying the presenters were "given the wrong category envelope," while promising an investigation.

"We appreciate the grace with which the nominees and Jimmy Kimmel handled the situation," the statement read.

The Wall Street Journal and celebrity website TMZ.com reported on Monday that one of the PwCaccountants responsible for handing out the sealed envelopes on Sunday had posted a backstage photo of actress Emma Stone on Twitter minutes before the mix-up.

The photo, from the Twitter account of Brian Cullinan, was later deleted but was still viewable on Monday on a cached archive of the page.

The Wall Street Journal reported that Cullinan'stweet read "BestActress Emma Stonebackstage! #PWC!" and was posted at 9:05 p.m. PT, three minutes prior to the envelope mix-up.

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Moonlightdirector Barry Jenkins and his team ascended to the stage looking startled after Horowitz's revelation.

"Even in my dreams this cannot be true," Jenkins said.

• Read more about the mix-up for best picture and other awards given out last night

Huge Oscar mix-up: wrong best picture announced

8 years ago

Duration 2:49

Presenters Beatty and Dunaway given incorrect envelope by mistake

The not-so-hidden inspiration

There were many standing ovations at the ceremony, but one of the loudest was for the surprise appearance of 98-year-old NASA valuable player Katherine Johnson, the inspiration for the filmHidden Figures.

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Johnson was introduced byTaraji P. Henson who portrayed her and her co-stars in the film about female black mathematicians and physicists who helped NASA in the U.S. space race with the Soviets.

HensoncalledJohnson "a true NASA and American hero" as the woman who worked for the space agency for three decades and previously received a presidential medal of freedom thanked the audience.

The tourists

At one point, host Jimmy Kimmelpranked an unsuspecting gaggle of tourists. The group thought they were going to an exhibit but ended up in the front row with Meryl Streep and Casey Affleck.

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The tourists awkwardly interacted with movie stars, with some shaking hands with Ryan Goslingand others rubbing Mahershala Ali's Oscar award like it would grant them three wishes.Kimmel even had Jennifer Aniston give her sunglasses to a woman with a selfie stick.

The bit was inspired, but eventually dragged on and on ... and on.

The 'feud'

Kimmel has had a longstanding fauxfeud with actor Matt Damon, which spilled over into the Oscars.

"I've known Matt for a long time now," Kimmel said. "I've known Matt for so long, when I first met Matt, I was the fat one."

At various points in the ceremony, Damon tried to trip Kimmel as he was walking the aisle. Kimmel, meanwhile, sent up Damon's We Bought a Zoo as part of the night's periodic segments on films from the past which stars admired.

When Damon finally went up to present a screenplay Oscar, Kimmel commandeered the orchestra and personally initiated the so-called "wrap it up" music every time Damon tried to speak.

The boycott

Iran'sThe Salesmanwon for best foreign language film, but its director Asghar Farhadi, who won the same award in 2011 for A Separation,was not there to accept the award.

Farhadi boycotted the ceremony in protest to U.S. President Donald Trump's recent executive order, struck down by the courts, which aimed to bar entry to the U.S. to anyone with citizenship from seven Muslim-majority countries.Farhadi is from Iran, one of the seven countries listed in the ban.

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"My absence is out of respect for the people of my country and those of other six nations who have been disrespected by the inhumane law that bans entry of immigrant to the U.S.,"Farhadi said in a statement read by Iranian astronautAnousheh Ansari,who accepted the award on his behalf.

Iran's foreign minister Javad Zarif praised Farhadi for his win and his stance.

The tweets

Kimmel predictably reprised his show's Mean Tweets segment, with perhaps the funniest Ryan Gosling's reading of a foul-mouthed jealous type.

Kimmel had earlier in the show joked that Trump would tweet about the Oscars "during his 5 a.m. bowel movement," taking a jab at Trump's early morning Twitterstorms.

But rather than wait, he decided to tweet directly at the president. Live on TV. At the Oscars.Twice.

Trump has yet to reply.