He may be a Grammy-nominated pop sensation, but don’t let Mexican singer Cristian Castro‘s well-groomed looks fool you. He’s a bit of a rockero at heart.

Castro is starring in a heavy metal inspired commercial for Pepsi in Argentina to promote the company’s “one, two, three, four, five” campaign.

Shot in Buenos Aires and airing in the region, the ad starts off with a heavy metal band strumming their guitars on the stage and leaping into the audience.

When one of the longhaired, tattooed members of the band takes a break open a Pepsi, Castro—looking all dapper in a white tuxedo—appears and starts crooning one of his classic pop hits. He then morphs into a black leather-clad rocker with punk hair.

“It’s a campaign that strengthens the ties between Pepsi and music, showing a completely surprising and fun side of a mega star like Cristian Castro,” says Lopez Marti, Pepsi’s marketing manager for the Southern Cone.

The campaign coincides with the upcoming release of Castro’s new album, “Mi amigo el Príncipe,” due out on November 1. It’s the follow-up to “Viva el Príncipe” an homage to Mexican singer José José, where Castro sings accompanied by a full orchestra.

But this isn’t Castro’s first “full metal jacket” experience. Last month, he created a hilarious video with mun2 that featured his secret life as a “Metalero.”