Might Vincent Chase suddenly not be the best looking person in his Entourage?

Sources confirm that Zac Efron has landed a guest-starring role on the hit HBO series.

No word yet on the exact role Efron will play, but the show is known for depicting celebrities simply as themselves.

"He was filming a scene and talking on his cell phone," said an onlooker near the Beverly Hills Niketown store, where Efron was being filmed. "None of the other Entourage cast was here. He was really nice."

Season six of the show premieres on July 12.

Efron is far from the only famous guest star lined up. The following celebs will also appear on the series:

• Lil Wayne
• Tom Brady
• LeBron James
• Aaron Sorkin
• Autumn Reeser
• Kate Mara