What’s better than Zac Efron doing the Macarena? Zac Efron doing the Macarena — nearly naked. In the newly released red band trailer for the heartthrob’s upcoming flick, Dirty Grandpa, Efron’s character dares to bare (nearly) all one wild night.

In the comedy, Efron stars as Jason Kelly, a responsible lawyer who has to accompany his grandpa Dick, played by Hollywood legend Robert De Niro, down to Florida after Dick’s wife passes away.

The only thing that Jason didn’t anticipate, however, was being his alcohol-swilling, foul-mouthed grandpa’s wing man.

“I haven’t had sex in 15 years and I want to f—k f—k f—k f—k f—k,” De Niro’s character declares while the pair are out in public hitting a few rounds of golf.

Efron’s uptight Jason doesn’t stand a chance steering clear of his grandpa’s shenanigans when they get pulled along to party with some attractive locals.

“For one night, stop worrying about your wedding,” De Niro’s Dick Kelly tells Jason. (In the flick, Jason is engaged to Julianne Hough’s character, Meredith Goldstein.)

The result is one booze and drug-fueled night with Dick and Jason partying down in Daytona Beach, Fla.

At point in the trailer, Jason strips down to nothing but a stuffed animal hornet tied around his waist as he does the Macarena.

“I just smoked crack?” he asks, bewildered, a moment before.

Watch the NSFW red band trailer above! Dirty Grandpa is set for release on Jan. 22.

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