Zac Efron Adds to Entourage

As Zac Efron is about to learn, Hollywood isn't High School.

The teen star is joining the boys of HBO's Entourage, where he'll be added to the laundry list of celebs to cameo on the Mark Wahlberg-produced hit.

Efron shot scenes on Tuesday at Beverly Hills' Niketown. The show stars Emmy award winning Jeremy Piven, Adrien Grenier, Kevin Connolly and Kevin Dillon.

Previous guest stars have included Leighton Meester, Jessica Alba, Luke Wilson, Brooke Shields and Ed Burns.

(Photo: Pacific Coast News)

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• TAGS
• Brooke Shields
• Entourage
• HBO
• Jeremy Piven
• Jessica Alba
• Zac Efron