Zac Efron: High School Musical superstar, oft-shirtless wonder...up-and-coming recording artist?

The Internet is buzzing after the Neighbors star posted a photo on Twitter yesterday (Nov. 3) in front of a mic wearing a Jimi Hendrix tee, captioned simply: "Recording."

This isn't the first time he's mentioned the word, either: at the end of October, he posted a mini-video of himself at a piano.

"Recording and someone told me this is @aliciakeys's Empire State of Mind piano- Couldn't resist. #thegreatestshowman," he wrote.

So, Zac The Pop Star coming or something?

It's always possible that he's contributing to the soundtrack of an upcoming film: he did sing for both High School Musical and Hairspray, after all. Any guesses?

While we analyze Zac's latest musical move, check out some of his best sonic contributions to date below.

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