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Going from casual to dressy in less than 60 seconds, Zac Efron left his hotel in New York City and we recently spotted him on his way to an interview with David Letterman on his talk show.

While joking around on The Late Show with David Letterman, Efron confessed that he was recently asked by a fan if he’s over the HSM songs yet. Zac said he replied, “‘Yeah, we sing them for two months straight.’ She grabbed my by the shirt collar and pulled me in really close.”

Efron continued, “She was like, ‘Two months? I’ve had this in my car for two years!’ And I realized that it’s gotten completely out of hand.”

And it was Sherri Shepherd on The View.

Gallery Info: Zac Efron leaves his New York Hotel to go promote his movie 17 Again on The Late Show with David Letterman.