Zac Efron (WireImage)

Zac Efron has reunited with his ex, Vanessa Hudgens. They split in December, and Efron was then linked to Rumer Willis. But he and Hudgens arrived together at the opening of Hollywood hot spot Eden on Friday night. Spies said Hudgens, in a tight black dress, and Efron “were inseparable all night, dancing, drinking vodka and canoodling.” Other stars at the party included Brittany Snow, Jesse McCartney and Paris Hilton with sister Nicky.