While Black Panther and Spider-Man will undoubtedly emerge as the breakout stars of Marvel's "Captain America: Civil War," they face stiff competition from a surprising, and very, very fashionable, contender: Vision's sweater.

The synthetic humanoid rocked the Internet last month with a classic pullover that might seem more at home in an episode of "Father Knows Best" than in a summer superhero blockbuster -- and there's good reason for that.

Talking with Vulture about selecting casual clothes for Earth's Mightiest Heroes, costume designer Judianna Makovsky revealed they had some early difficulties with the Vision, played by Paul Bettany.

"When I had the first meetings with [directors] Joe and Anthony Russo, we talked about the Vision trying to feel more comfortable at the Avengers compound and trying to fit in. What would that mean?" said the three-time Oscar nominee. "We started out with him more in comfort clothes, like sweats, or something really casual. So we drew it, and it just didn't look right. It didn't go with the voice, it didn't go with the attitude."

Luckily, however, Makovsky delved into the character's origins, which includes elements of Tony Stark's artificial intelligence J.A.R.V.I.S. "What would J.A.R.V.I.S. wear?" the costume designer said. "I thought he would be confident and elegant in his taste, almost perfect, so we decided to look into the men of the 1940s, like Cary Grant: very simple flannel trousers, elegant cashmere sweaters." They even topped off his look with the dandiest of all affectations, an ascot: "It's sort of hidden under his shirt, but it's there."

Makovsky talks about her approach to the rest of the team's casual clothes at Vulture. "Captain America: Civil War" opens today nationwide.