Mika makes Marmite pop music. Back in January, when Grace Kelly first leapt out of the radio, people rushed to instant judgment. Indifference was not an option. His album, Life in Cartoon Motion, is more of the same. It’s either winsome and irritating or a gorgeous blast of arch, witty, invigorating, left-field pop where no two songs sound the same, but all are naggingly familiar; where 1980s disco meets 1970s glam-rock and full orchestras are counterpointed by falsetto vocals.

“That was completely unintentional,” he insists. “When people say I’m savvy and musically calculating, that doesn’t abide with me. I’m not. I consider what I do quite normal. Whatever I do, I do because it feels right.” Mika, now 23, has been compared to Freddie Mercury. He certainly shares an exotic background with the Queen singer, who was an Indian Parsee born in Zanzibar. Half Lebanese, half American, Mica Penniman was born in Beirut and raised in Paris and London. He speaks English with a mid-Atlantic twang. His education was scarred by bullying, dyslexia and obsessive compulsive disorder (OCD). Factor in a precocious musical talent, a striking visual imagination and an ambiguous sexuality, and you have an outsider’s genesis resulting in music made by instinct, not corralled by genre or an idea of what is hip.

“I am an outsider, a watcher,” he agrees. “It wasn’t by choice. You have to be delusional not to want to belong. I had a really hard time for most of my childhood.”

The third of five children, Mica was evacuated to Cyprus during the Lebanese civil war in 1984. Moving to a thriving Lebanese community in Paris, he grew up in a matriarchy, with education the absolute priority. “If you are even just a quarter Lebanese, it will take over your life,” he explains. “The food, the music, the attitude, the openness of the household to anybody, the incense burning, the volume at which people talk, the flammable Arabic arguments that evaporate within 30 seconds.”

Music was omnipresent: Dylan, Joan Baez, the Byrds, Serge Gainsbourg, Tino Rossi, French children’s songs, Arabic oud instrumentals and the female vocalists Om Kalsoum and Fairuz. “As a kid, I had a fascination with patterns, which is why I loved melody,” he says. “I made mix tapes that weren’t organised by singers or style of music, but by emotion – melodies that make you happy and melodies that make you sad. I’d end up with Tino, Nina Simone and Shabba Ranks on one tape. To me, that was completely normal.”

This idyll was disrupted by the first Gulf war, when his banker father was trapped in Kuwait for seven months. One by one, the trappings of luxury – the housekeeper, the large apartment – had to be given up and the family moved to London. Mica, who had previously attended a small private school dressed in bow tie, matching shirt and shorts, his hair as long as a girl’s, was enrolled in the Lycée Français, in South Kensington. Dislocated and disturbed by what had happened, he was crushed by the school. His dyslexia got worse – so quickly that, within a year, he could barely read or write.

“I had a cruel teacher who made my life complete hell,” he says, still angry years later. “How can a system that bases itself on learning by rote cope with a dyslexic? And I had problems with other kids.”

Asked to leave at 11, he spent the next seven months painting and being taught to sing by an expatriate Russian. He always had a voice, though he dismisses talk of a five-octave range as “making me sound like the alien in The Fifth Element”. He made his stage debut at the Royal Opera House, and sang jingles for British Air-ways and Orbit chewing gum. It wasn’t about the money – he never charged enough – but about gaining a sense of self-worth.

“I loved it,” says Mica. “I clung to the idea that I was a real person, and this was my job. If I messed up, I cried, because it made me look like an idiot. I knew there were a hundred other kids who could do it. My mother was shocked by how seriously I got into it.”

He went to Westminster School, where a teacher showed him how to use visual aids to overcome his dyslexia, and the dunce turned into a straight-As student – despite twice being asked to leave when the family funds ran dry. His obsession with a musical career meant normal friendships were elusive. At 13, he blagged his way into a private record-company party for Diana Ross, sang five songs and forced the boss to have a meeting the next day. A few years later, Simon Cowell didn’t like his songwriting, but said his voice was unique. “He said he’d call me. When he didn’t, I called him every day for four months. He never took my call. I was holding onto everything and everyone I could. That’s the OCD. Once I have decided something, it has to be that way, and it doesn’t change. While it works for me, it has ruined personal relationships. My family understands me, but it causes problems with my friends, even with my crew on the road. Now I have a set bunch of friends. I am extremely faithful and I spoil them, and it is important to do that whenever you can.”

He is an obsessive collector of Japanese designer toys, toy theatres and illustration art (Jim Woodring watercolours and Tony Millionaire comic-book cards). If he finds a jacket he likes, he gets three. He wears three watches on his wrist, but only the Nike digital tells the time. “We are all obsessed with repetition, we just don’t know it. Pop culture is based on repetition, which is why Warhol was a genius.”

At 19, Mika had his first and probably last moment of self-doubt. His attempt to read geography at the LSE lasted one afternoon. Then he won a place at the Royal College of Music, even though he couldn’t read music. For the next 2½ years, he led a double life.

He needed to be exposed to music, to discipline and pattern, something to do at nine every morning, but he was never going to be an opera singer. “I was mediocre. In the evenings, I was writing pop songs or working as a waiter to pay my studio bills.”

When he went to a party at his grandmother’s in New York, a publisher put him together with the songwriter Jodi Marr. After a year spending his student loans on flights to Miami, begging floor space and cadging dead hours in the studio (the Bee Gee Barry Gibb fired his house engineer for giving Mika free time), he had five songs.

Instead of touting them around, he spent another year creating the concept of Mika, designing (with his sister) a distinct visual image with characters, a logo and photos, all packaged in a box tied up with ribbon. Although an illusion made of cardboard and borrowed time, it looked like a million dollars, and the highly commercial songs had company head hon-chos scrabbling for their chequebooks. “There is a liberating vulgarity to the way you can do business in New York that you can’t get away with in London , ” Mika laughs. “Here, they called me an irritating prat; there, I had chutzpah.”

Mika signed with Tommy Mottola (the former head of Sony) in America and with Universal in the UK. Although America is proving a harder nut to crack, in Britain the single Grace Kelly went to No 1, has sold more than half a million and is still in the Top 40.

“Life in Cartoon Motion was my school-yard album, and I wanted to catch that freshness,” he says. “I knew I had only one chance. The glorious thing about a pop song is its populism – a lot of people shy away from that, but I think it is empowering. I have this fascination with the mundane: I love soap operas, the idea that you can take the freak and write about them in a pop song. Take Big Girl [his amusing paean to the larger lady]: she is an outsider, but, for three minutes, I put her on a throne, paint this incredible multicoloured backdrop and turn her into something she never is. It’s supposed to be funny, but not in a Little Britain way, in a human way.”

Mika is in this for the long haul. It is all he has ever wanted; he has never been frightened to fail and is confident about taking his live show to the big summer festivals. “I’m not exactly indie rock, am I?” he grins. “Do you think I’ll get glassed?”

In July, he is also opening an exhibition of his album artwork, of which he is fiercely proud. “I want to be able to tie it all together, which is why we’re putting together this exhibit, just to show the process behind it.” He adds hastily: “It’s not supposed to compete with anything being shown in the West End or Hoxton.

It is art with a purpose – illustration artwork that works.”

This year, Mika has already survived months of ocean-crossing promo work, being the saviour of pop music. And it’s only May. He shrugs: “In 10 years’ time, I will be doing the same as I am doing now.

A pop star – that’s so shit. I don’t think I’ll ever be a member of that club.” Once an outsider ...

Artwork from Life in Cartoon Motion can be seen at Blink Gallery, W1, July 11-14.

Mika is performing live at Glastonbury, June 22-24; T in the Park, July 7; Somerset House, July 17; The Big Chill, August 3; V Festival, Staffordshire, August 18; V Festival, Essex, August 19

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