That's an odd looking cigarette!

Zac Efron was back on the set of his latest film We Are Your Friends in the Hollywood Hills yesterday, and he appeared to be puffing away on a joint! Or does he hold his cigarettes that way?

The actor and the Fast and the Furious star called it quits recently when their fling ended because the actress was reportedly still hung up on ex-girlfriend Cara Delevingne. Not only that, but the High School Musical star wanted a more intense relationship than the brunette beauty was ready for. "Zac has an addictive personality, which rolls over to his women. He invests in something and falls hard — fast. He really fell hard for Michelle, and she wanted to just have fun and not have a super serious relationship. Plus, Michelle is interested more in women than men — so that was an issue as well," a source tells Hollywood Life.

Wonder who he'll date next?