They are, according to the taxi-driver, “some sort of a myth. Young people, old people . . . everyone knows a story about them”. They are Les Rita Mitsouko, the art-rock duo that has fascinated France for nearly three decades, and he is taking me to Pigalle to meet them.

Les Rita Mitsouko are hardly known outside of France, but they are legends within it. The band formed in 1980 by Catherine Ringer and Fred Chichin have had million-selling quirky pop hits such as Andy and Marcia Baila (the most played song on French radio), a film made about them by Jean-Luc Godard, their videos directed by Jean-Baptiste Mondino (the ne plus ultra of French fashion photography) and their costumes designed by Jean Paul Gaultier and Agnès B.

But it is their volatile temperament that France loves them for most. In 1985 Serge Gainsbourg called Ringer “a filthy whore” on a television chat show after she talked about her brief career as a porn movie actress. “I used to admire you, but now you’re a disgusting old parasite,” she retorted.

I contacted Russell Mael of Sparks, the American duo that inspired Les Rita Mitsouko in the first place and who worked with the band on their 1988 album Marc et Robert, to find out what to expect. “They’re lovely people, but it takes a lot of guts to tell them not to smoke in the studio,” said Mael. “We were with Catherine once when a fan came up and asked her for an autograph. She punched his lights out.”

By the time I get to Pigalle the nerves are kicking in, particularly as I’ve been asked not to talk about their private lives in any way. I arrive at the band’s office, above a nightclub called La Cigalle, where Maurice Chevalier once held down a residency and where the band will be playing later on. Then Ringer and Chichin arrive, friendly and speaking perfect English, and it looks as if it’s going to be easier than I thought.

Ringer, who at 50 has the Parisian woman’s ability to wear her age with allure and a touch of ferocity, is the daughter of an artist father and an architect mother. She met Chichin in Paris in the spring of 1979, on the set of a Situationist play she was starring in. “He told me that what I was doing was s***,” she says, lighting the first of a chain of cigarettes. “He said that I had to leave and work with him. We knew that we wanted to make pop-rock music, and we both liked the Stooges, Bowie and the Velvet Underground, but beyond that we had no idea what we would sound like.”

Naming themselves after the Japanese cover star of an album by Sparks, the pair turned a Parisian squat into a makeshift studio, using his knowledge of production and electronic music and her grounding in theatre to create a musical vision – flamboyant, irreverent and without boundaries – which they unleashed at various underground nightclubs.

“At first people didn’t like us at all,” Chichin says. “In France there is always an ideology in music – you know, you can’t play that because it means that, and so on. There is a big problem with rock in France because the French are so conservative. But we kept going and slowly people understood us.”

For much of the 1980s Les Rita Mitsouko existed at the hub of Parisian bohemia. Combining French chanson with electronic rhythms and Bowie-style art rock on their eponymous 1984 debut and The No Comprendo (1985), Ringer and Chichin became superstars.

“We believe in the magic of meeting at the crossroads,” Chichin says when I ask how they came to work with Godard and Gaultier. “We never chase after them; it just happens. When you don’t look for magic it may happen anyway.”

Ultimately, it was age that was to make Les Rita Mitsouko respectable. The only shocking thing about Variety, their new album that has been recorded in both English and French, is how middle-of-the-road it sounds. I wonder out loud if this new mellowness is an indication of how their personal relationship dictates their professional one.

“That is not interesting to us,” says Chichin, politely but firmly.

“Stop,” says Ringer with controlled menace. I do as she says.

The age range of the audience at that evening’s concert – between 10 and 70 – shows how they have become part of the Gallic identity. Like Gainsbourg, Les Rita Mitsouko embodies a certain chic defiance that the French love. “The first time we went to a record company the guy there said: ‘Your music will not work for this business,’” Ringer says. “So I said: ‘What will work?’ He replied, ‘Hey, that’s the magic of this business! We don’t know!’

“Ever since then we have decided to do exactly what we want because doing what you think other people want leads to disaster.”

Variety is released by Because Music. Les Rita Mitsouko play the 100 Club, London W1, on July 11. www.the100club.co.uk

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