The 27-year-old star has been filming his upcoming comedy Dirty Grandpa in Georgia since late April, and plenty of nearly naked photos have surfaced from the production. So when a scene called for Efron to strip down to a tiny thong, the star reportedly refused -- probably because he knew they would surface online in a matter of minutes.
That's when the producers had to call in Efron's butt double (which, admittedly, would be amazing to have on a resume).
To his credit the former High School Musical star did strip down to a pair of flesh-tone briefs, but he left the real thong-wearing, motorcycle-riding to a professional.
When Efron isn't busy getting naked in front of the cameras, he appears to be spending quality time with his girlfriend Sami Miro. The young model was spotted visiting her boyfriend on set, and the couple even found time to go jogging on the beach.
The couple also reportedly took Efron's one day off from shooting to take in a ghost tour of historic Savannah.
In the film, Zac plays Robert De Niro's uptight grandson, who gets tricked into driving the perverted former Army general to Florida for spring break right before his own wedding. Parks and Recreation star Aubrey Plaza and Dancing With the Stars' Julianne Hough co-star. The film is slated for an August 2016 release.