Zac celebrated the NBA All-Star Weekend by attending the game and a party on Feb 19:
diplo tweeted a pic from the game (although he was not supposed to be):
The paps tried to catch Zac after the game but all they got was a shaky video...
The LA Times had a blurb about the party in the evening:
After the premiere screening atop the hotel at club Drai's, West gave a surprise performance for the lucky crowd, which included Leonardo DiCaprio. His set raged for seven songs before being cut off because of sound ordinances, but was thoroughly enjoyed by couple Ashton Kutcher and Demi Moore, as well as a reunited, maybe-back-on Zac Efron and Vanessa Hudgens.
Viper Viiperi posted another (better) pic of Zac & him from Calvin Klein Fashionweek and mentioned meeting Zac in a recent article:
You recently posed for a photo with Zac Efron at the Calvin Klein show in NYC. On his website, Perez declared that you are “hotter” than Zac. Is Perez right?
Well, that's something I don't know. I'm a fan of Zac's work and I love many of his movies. Having met him now, I'll say he's really chill and seems to be a cool guy. I can't wait to see his new movie [Art of the Steal] where he plays the bad guy this time.
And last but not least, Zac attended Rihanna's birthday party on Feb 20, 2011. From People:
Rihanna celebrated her 23rd birthday Sunday night by rocking out with some of music's biggest names – but she also found time for some quiet celebrating with old friends. [...]
"She [gave] Ryan Phillippe and Zac Efron huge hugs," the source says, adding that the two actors hung out together and chatted throughout the night.
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