Zac Efron Has a Hangover

Zac Efron keeps it casual in a jean button up at the premiere of The Hangover held at Grauman’s Chinese Theater in Hollywood on Tuesday night (June 2).

The Hangover is about three groomsmen who lose their about-to-be-wed buddy during their drunken misadventures, then must retrace their steps in order to find him. The movie hits theaters THIS Friday.

Zac, 21, was seen earlier today filming some scenes for HBO comedy Entourage.

10+ pics inside…