From the moment the “House of Gucci” trailer was released, Jared Leto’s transformation from svelte, long-haired actor to pudgy, balding fashion designer Paolo Gucci has been the talk of the film world.

Leto’s Paolo is the family black sheep — a dreamer with a vision that deviates from the fashion house’s tasteful colors and designs. Hours of makeup each day went into Leto’s look for the Ridley Scott movie, which hits theaters Nov. 24. The concept began with prosthetics designer Göran Lundström, who worked off a 3D scan without having met the actor. “I didn’t know his hair color, his hairline and skin tone,” explains Lundström, who had just three weeks to prepare.

Instead, Lundström relied on pictures and videos of Leto: “He had so much hair — thick hair and a low hairline.” The designer started piecing together a puzzle that included a three-piece bald cap that ended in the middle of Leto’s forehead. “It took us an hour and a half just to cover his hair,” Lundström says of the fitting process. In addition to the eight prosthetic pieces, Leto wore a wig. The actor suggested adapting his own mustache into the look.

Like the rest of the star-studded cast — Lady Gaga as Patrizia Reggiani, Adam Driver as Maurizio Gucci and Al Pacino as Aldo Gucci — Leto lived as much as possible in character during shooting. “We usually apply makeup on set, but Jared wanted us to apply this at a separate location. So, he would show up on set as Paolo Gucci,” says Lundström.

Gaga and Driver had their own makeup and hair teams, but makeup designer Jana Carboni oversaw the looks, collaborating with the actors’ teams and presenting mood boards based on her extensive research of photos, books and of course, Vogue Italia. “What you saw in ’70s America was not the look of ’70s Italy,” Carboni says. “Italy was more conservative, so it was a different look.” By the ’80s, Carboni notes, Italian women had grown confident in their fashion sense, and by the ’90s they had achieved independence. “They could embrace beauty and confidence and cleverness and not be ashamed of that,” she says. That spirit is reflected in Patrizia’s makeup arc.

For Camille Cottin, who plays Maurizio Gucci’s lover Paola Franchi, Carboni crafted a contrasting look based on wealthy Italian women in the ’80s, specifically from Milan. Inspired by a mix of Catherine Deneuve — an icon to Italian women — and actor Monica Vitti, the designer gave Paola a sun-kissed tan for an Italian glow. “Patrizia wasn’t supposed to be in the Gucci family because of her background, so she was always off,” Carboni says. “With Paola, she came from money. She was rich but wanted power.”

The designer says that Paola’s blond hair helped connote poshness. “We thought about her wig, designed by Giuliano Mariano, a lot. We wanted it to be icy, not yellow. The roots were darker, so you could see the depth of it and you could see how the light reflected off of it,” Carboni explains. “When you see the two women together, they’re opposites. It’s a dark versus light side, but they’re both trouble — strong women but very different.”