In Alan Moore and Dave Gibbons’ classic 1986 graphic novel “Watchmen,” the superheroes and vigilantes make their own costumes. This gives every look a level of accessibility that’s not often a consideration for big-budget action projects, but was a theme that needed to be carried over into HBO’s adaptation of the award-winning comic book.

Meghan Kasperlik, who came up as an assistant costume designer on blockbusters such as “The Dark Knight Rises” and “The Amazing Spider-Man 2,” was tasked with scaling back on a number of usual genre factors to make sure the characters in the TV series “looked appropriate to the ‘Watchmen’ world and not the world of superheroes we’re used to,” she says.

In the show, technology has advanced at a slower pace: Personal computers and cellular phones are not staples; climate change has not ravaged the planet to the same degree it has in real life; and members of the police force wear masks and have to get permission to unlock their weapons. All of these elements affected the style and materials of costumes, to a degree. But there were more important character considerations too. For instance, Regina King’s Angela, aka Sister Night, is living a double life.

“In my first meeting with Regina, we had a lengthy conversation about how we see Angela, how we see her progressing in the season, [and] if we don’t want anyone to know that Angela is Sister Night, we have to be adamant that Angela doesn’t wear black leather,” Kasperlik says. “She does wear black, but we very much limited [that color], especially early on, so the audience could see her as Angela and not as Sister Night.”

The Sister Night costume was one of many that were hand-constructed for the show and had to include doubles that had hidden pads at elbows and knees for heavy action, as well as “action gussets in the shoulders and under the arms so you can do more fighting without tearing, [because] leather is only going to stretch so much,” Kasperlik says. Although Sister Night’s coat looks and moves like one piece, Kasperlik says it’s actually a jacket and a skirt that detaches for easier mending or other adjustments when needed.

When Kasperlik signed on for the series, post-pilot, she tweaked Sharen Davis’ original Sister Night costume design to make it more accessible for the amount of action the character would be performing. “The way the hood was sitting wasn’t really working for everything,” Kasperlik says. “It wasn’t hitting the face at the right point, and it wasn’t staying on the head when it needed to.”

She initially changed the type of leather, but even that wasn’t enough, as partway through the day, when things started to heat up on the Atlanta set, the costume began to lose its shape. “At lunch I took it to the tailoring shop and added Neoprene to it — it was basically a lining of Neoprene — and it beautifully held the hood up on the head when we were doing stunts,” she says. “It was a fantastic surprise in a moment of ‘We need to fix this to make it look good today’ that actually fixed it for the rest of the season.”