This Friday, Zachary Levi hits theaters as the foster-teen-turned-adult-superhero Shazam! Naturally, that comes with a very specific visual style for the part, one that requires both a body transformation and getting the costume just right in order to nail the look of that particular superhero. The finished look seems effortless on screen but takes months – even years – to get right behind the scenes.

I spoke with Shazam! director David F. Sandberg last week about transforming Zachary Levi into the bemuscled, Golden Age costumed superhero and he said the body transformation part wasn’t as difficult as Levi “was actually really into working out and eating healthy.” I mentioned that I had rolled my eyes when the first leaked images of Levi in costume hit the internet and immediate speculation started swirling that his muscles weren’t real. Even with the most ripped superhero, spandex costumes require a thin foam rubber suit underneath to keep the spandex from flattening out those hard-earned muscles, making them lose their definition on camera.

Even with that, Sandberg explained, getting the look of the costume right took much longer, and sure, there’s that padding, but none of that padding works without the body underneath being equally heroic:

Absolutely. You want them to be able to look realistic but still mimic that comic book. There’s lots of wrinkle removing in post – you know, you sit down and your suit bunches in a weird spot…and it’s not something you’d see in a comic book, so you have to get rid of it. But the person under the suit, that’s all real, even with the thin padding to keep the shape under the spandex.

Speaking of that costume, Sandberg admitted it was a challenge to get the design to appear more like Shazam’s old-school, Golden Age costume while still being able to stack up to modern times. Was it tricky to find that balance going for a more matte finish?

It was, it was. You want it to have a little bit of texture – after all, you want him to be able to stand next to the Justice League and not look completely out of place. But you’re right, it was more Golden Age so from afar, it had that more old school, flat finish. It was tricky to get that balance right on camera.

The finished result is that Levi looks like he could easily throw a baddie halfway to the moon, but still maintains a look of playfulness and classic heroism. Costume designer Leah Butler, who has worked with Sandberg before, deserves a ton of credit for getting the look and feel exactly right.

You’ll have to see how it all came together for yourself (you can read our review here) when Shazam! hits theaters this Friday. Get your tickets now!