Perhaps the most striking costume in HBO’s Watchmen is reflective mask shrouding Looking Glass (Tim Blake Nelson). Most of his outfit is nondescript — a jacket, shirt, and pants in various shades of grey — but his mask is mesmerizing, as if it’s made out of liquid chrome. The texture is so shiny and reflective that other characters regularly use his visage as a mirror.

To get the scoop on exactly what Looking Glass’s mask is made out of (and see if it’s as achievable as the other superheroes’ looks seem to be), Polygon spoke to Watchmen costume designer Meghan Kasperlik. As it turns out, it’s not quite as within reach as you might hope (I want that mask for myself!), though lamé will do the trick in a pinch.

When it comes to what the look is trying to accomplish, Kasperlik tells us, “[Looking Glass] uses the mask more as his shield and he uses it to disguise himself, but it’s also kind of this barrier against everyone else.” No matter how that shine was accomplished, “it was important for him, for the integrity of the character, to always have the mask on.”

Kasperlik used a variety of methods to accomplish the reflectiveness, rather than a single silver mask that could do the job. “We had five different masks,” the designer says, explaining that exactly what Nelson was wearing would change depending on the demands of the scene. Some of the masks were for motion tracking, featuring a special print that would aid with motion capture and tracking, keeping track of the orientation of Nelson’s face at all times. Others were purely green screen or spandex, while yet another — the only mask that wouldn’t require the reflectiveness to be added via CG later — was made of lamé, a type of fabric that has metallic fiber woven throughout it, meaning only one of the actual masks used during shooting was that distinctive silver.

The CG effects on Looking Glass’s mask not only added color to the reflections but made sure that, via motion tracking, “all of the anatomical features were [there]; you could see the shapes underneath without giving away his eyes and his actual mouth.”

On top of that, the use of CG ensured that Nelson could actually see. One of the masks was completely solid, but for the sake of visibility and “to be able to connect with the other actors,” Kasperlik explains that they ended up building a mask with mesh where the eyes would be.

While it’s a disappointment to know that Looking Glass’ look isn’t quite replicable in real life unless you’re willing to wear a full head of (likely low-visibility) shiny lamé, the CG-heavy process for getting Looking Glass looking great is another way Watchmen is pushing the envelope of what’s possible on TV.