The Rock Shows Us His Crazy Buff Bod … From When He Was 15!

We didn't peg Dwayne "The Rock" Johnson as the type who was a scrawny, string bean of a kid, but we didn't expect him to be Mr. Superbuff either!

The wrestler-turned-action movie star posted a vintage photo of himself on Twitter as part of the Throwback Thursday trend — and he was one jacked 15-year-old! He had amazingly broad shoulders, muscular arms, and tight abs as he struck a tough guy pose, shirtless of course, next to his 1980s boom box. And the pièce de résistance? Well, other than his dark head of hair, was … a mustache!

[Related: Dwayne Johnson Maintains His Tough Guy Status Even After Emergency Surgery]

"We all start somewhere," the 41-year-old, whose new reality competition series "The Hero" debuts Thursday on TNT, wrote with the photo. He also used some amusing hashtags, including "#creepymustache," "#boombox," and "captainwhiteshorts."

When we first saw the photo, we actually questioned whether he could really have been 15 at the time — he just looks so … mature! — and apparently we weren't the only ones.

[Related: The Rock Insists 'The Hero' Will Be Epic Upon Epic]

Commenter @elizabeth4everr wrote, "Wow you don't look 15...more like 20-25…lol. And @YashKandhari noted, "hahahaha he was already 6'4 at the age of 15! Beast!!"

We must agree — pretty fierce for 15.

More Celebrity Features on Yahoo!: