Reunited: Justin and Cameron's 'fairytale' kiss

The longtime pair split late last year, and though there has been a report of at least one brief Hollywood encounter, the Shrek screening marked the first major media event at which they've been photographed together since the breakup.

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Diaz, who voices Fiona, arrived first, making her way down the green carpet in a bright-salmon Chanel dress, staying close to costar Mike Myers.

Timberlake, who plays would-be king Arthur, walked the press gauntlet just steps behind Diaz, though the two didn't appear to make eye contact during interviews.

But, later, at the cast photo, greeting each other with big smiles and sharing a hug and kiss.

Although they were more than cordial, the moment was appeared little uncomfortable.

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The Shrek headliners turned out in full force for the premiere.

In addition to Diaz, Timberlake and Mike Myers, the star attendees included Julie Andrews, Antonio Banderas, Rupert Everett, as well as Eddie Murphy, who talked about what sets "the Third" apart from the first two.

"I think they've incorporated all the characters more," Murphy said.

"The story isn't so much Shrek and Donkey and Fiona. It's everybody, everybody's got funny stuff to do. But what's remained consistent is the sweetness: a sweet little message in the back, and what's in the front is very, very funny and inventive."

The new film finds Shrek and Fiona living happily ever after in the land of Far Far Away.

But then the king dies and Shrek is asked to take the throne.

The problem is, he doesn't want the gig, and evil Prince Charming does.

Mayhem ensues, including an accidental body-switching for Murphy's "Donkey" and Banderas' "Puss in Boots."

"I could say that I did my own stunts in this movie," joked Banderas, who attended the premiere with actress-wife Melanie Griffith.

"Let me just say it was very dramatic being in his body for 15 minutes. I survived it, though."