So what brought these Twitter pals, whose recent tweets seemed to suggest they had headed Down Under together?
The former That '70s Show star and Derek Jeter's ex were on hand for the opening of the new nightclub Marquee at The Star Sydney Casino & Hotel.
But Valderrama and Kelly certainly weren't the only famous faces at the star-studded event.
Those in attendance included Ashlee Simpson, Kellan Lutz, Joe Jonas, Slash, Paris Hilton, Abbie Cornish, Redfoo of LMFAO as well as Nick and Vanessa Lachey, who easily reminded fellow partygoers that they are expecting their first child together.
The new $20 million hot spot is an off-shoot of the Las Vegas club of the same name.
It will officially be open to the public tonight with Will.i.am of the Black Eyed Peas performing.
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