LONDON — French men’s wear designer Alexandre Mattiussi has opened his first Ami store in London — and the fifth worldwide — and it has the whiff of a cool Parisian apartment.

The store, at 75 Duke Street in Mayfair, is housed in what was once a bar and a gallery space. It spans 2,580 square feet over two floors and was designed by the Parisian architects, Studio KO, who are behind all the Ami store concepts.

The feel is that of a Parisian apartment, with the ground level bathed in light thanks to floor-to-ceiling windows while other walls are covered in mirrors or feature whitewashed, exposed brickwork.

The natural wood floor has been hand-painted with a black geometric motif — based on an ancient Roman mosaic — a version of which features in all the stores.

The lower level has concrete floors, chipboard ceilings and a ceramic tiled alcove. Fitting rooms, meanwhile, come with laminated cork interiors and heavy canvas curtains.

Fittings include dramatic Azul Bahia marble-topped display units, wooden shelving and rails of polished brass resembling pipe work.

Atmosphere has always played a key role for Mattiussi, who was a ballet dancer until the age of 14. He said he was attracted to the idea of “the spectacle” as much as the dancing itself.

“The curtains opening, the music, the lights, the makeup, the set, the applause at the end, it’s about telling a story,” he said during a walk-through.

To wit, the space is peppered with domestic details including portraits, an old-fashioned television and a bust wearing Mattiussi’s signature red beanie hat.

“The sculpture is a copy of one from my father’s house,” said the designer, “and I always wear a beanie as I have crazy hair.”

In London, Mattiussi said he expects to attract a similar clientele to Paris. “I design my collections for myself and my friends and always ask them what they want to wear. It’s like when you invite people for dinner and ask them what they want to eat.”

“I always thought it was weird to design things I couldn’t afford, like a 3,000 euros, or $3,413, sweater; you feel disconnected,” he said, referring to brands such as Dior, Givenchy and Marc Jacobs, for which he worked before starting his label.

“With Ami, I wanted to create a sophisticated wardrobe but in a very democratic way, both in the price points and the look.”

His clientele isn’t just male. Mattiussi’s shows often feature women, with his clothes attracting a sizable female fan base. “I have so many girls around me; I feel it’s sexy — and natural — to dress them in men’s clothes, it makes sense.”

And while he maintains he doesn’t feel ready to do women’s wear, he said he recently created suits for the French singer Héloïse Letissier of Christine and the Queens. She performed with Madonna on the Paris leg of the latter’s Rebel Heart tour last year.

He said London was a natural location for a store. There are already three Ami stores in Paris, and one in Tokyo, which launched last September. The store had a soft opening this week and opens officially May 4. The designer declined to reveal first-year sales projections for the store.

“In London, you can feel a great energy in the way people dress and express themselves,” Mattiussi said. “From a global point of view, it is definitely the best European destination to buy and discover fashion and we are very proud to be here. It has also been one of our biggest markets from the beginning with lots of support from Mr Porter,, Harrods and Selfridges.”

Exclusives include an oversize sweater bearing the same motif as the wooden floor, black sneakers and a raincoat in black waxed cotton. “Not that I’m saying it’s raining all the time in London,” he said.

There are, as yet, no plans for further expansion. “We are only five years old,” he said. “We really believe Ami could be everywhere in the world. It’s just going to take time, but as I always say. ‘This is the story of my life,’ so I have time.’”