By now it is clear that Mika is not as other artists are. His surname could just as well be 'Singular'. Enveloped in an imaginative musical world of his own creation, he is one of the few male pop stars of his age that doesn't run with the pack. Classically trained, racially mixed and prone to theatrical physical gesture, he has become a scion of ambitiously delivered self-expression. He says his music can be condensed easily, 'the basic principals are that it is joyful and empowering and doesn't kowtow to fashion or convention,' calling to mind an old and almost forgotten pop notion: individuality.

If his debut album Life In Cartoon Motion was the brazen calling card of this individuality, then its follow-up is the maturation of an unapologetic pop sound that he has made all his own. The octave-straddling voice, the virtuoso piano-playing, the rumbling rhythms and explosive finales, the larger-than-life storytelling to get to the nub of human insecurities and the striking technicolor pop productions are all in place. 'My biggest mindset when I set about making it was not to be reactive,' he says, 'I had to go back to the start, when people hadn't given me their opinions on what it is that I naturally do.' On first listen, there is only one word to describe the second instalment of his kaleidoscopic pop dream. That word is 'audacious'.

Mika opened his pop career with the defining single "Grace Kelly." It has sold almost 3 million copies worldwide and was only the second British single to top the chart on downloads alone. His total single sales from Life In Cartoon Motion add up beyond six million. The album itself bagged over 5million till receipts. Mika was nominated for and won awards from the Brits, the Grammys, the Ivor Novellos, Capital Radio, Q magazine, The World Music Awards, BT and Vodaphone, Virgin Media and MTV's Europe, Asia, Australia and Japan, amongst others. But the statistics only hint at the strident grip he boldly took on pop music when he entered its fray; they are the neat vindication that one of pop's biggest outsiders could conquer from within.

Prior to his signing to Casablanca/Island, Mika had been lambasted and shunned by major record label after major record label – a story well-documented in the lyrics to "Grace Kelly" – his victories were a triumph of vision and substance over momentary fads. For a pop star of his age he had deliberately taken a difficult route, favouring the idea of longevity by sticking to his own pop principals over an instant return by pleasuring the suits.

Second time out, the songs may be different, but the attitude remains the same. From the instantly huge chorus of "We Are Golden" through songs that in turn call to mind 40s Disney ("Toyboy") and a touchingly modern update on 80s power-pop ("Touches You"), there is a breadth of vision here that deigns to rub up against the classics. From rollerblading disco anthems ("Rain") through melancholy reflections on personal trauma ("Dr John"), his music is underpinned by an open-hearted and accepting idea of what living in the 21st century means in all its contradictions and complications. Another thing about Mika? He is not afraid of enormity. While in rock music, those in thrall to the template of U2 have become revered for their attempts to harness arena-sized emotion, in pop, largesse has all but disappeared, left to a brace of young women that will reveal enough flesh for a lad's magazine and would never really buy one of their own records. Mika is here to reclaim it.

As the blizzard of acclaim, sales and personal achievement of hitting a raw public note of approval with his debut album began to clear, Mika started to look for an apartment in LA to conceive, shape and write its follow-up. He found a beautiful space to decamp from his London basement, to work with his producer and musical co-conspirator Greg Wells. And then his mother stepped in. 'She told me not to get too comfortable,' he says now. Sage words a son cannot choose to ignore. So he moved back into the cheap hotel he had fashioned his debut from. When it came to part 2 of the riveting Mika tale, he decided to unlearn everything that his glittering two years of limelight had taught him. 'This is still bedroom music to me. It's about sitting at a piano and saying what I have to say.'

'The first album, to me,' he continues, 'was about childhood. It had that innocence. For this one we have moved on ten years and into the adolescent mind. Adolescence is one of the most glorious times in your life. It is when those life experiences, like sex, drugs and relationships, are still new and untainted. If I was to think about these things in song I knew that I had to become more personal.' Mika has stepped aside from the character-based storytelling of Life In Cartoon Motion for album number 2. 'I still believe in mystery and I don't feel like I have to justify anything about my life anymore. Because it is all in my songs. Songwriting for me is a way of catching up with myself.'

Not that he didn't find the idea of writing in the first person daunting. 'Joyfulness has a risk attached to it. It's why it is so tempting to and dangerous to forget about the first time things happened. I had to confront the reality of writing a song about myself. It was something that terrified me. If I wasn't going to paint myself into the position of being a 40s review singer, this was something I had to do.' Accompanying this feeling was Mika's old tenet of not being afraid of criticism. 'As a popular songwriter, the myopic view is that you are not allowed to step out of where pop songs should exist. Otherwise you will be mocked. But to me, the perfect pop song should feel like trying on the jacket that you always dreamt of owning.'

Part of the beauty of Mika has always been attempting to trace the correlation of his own personal insecurities or hang-ups into the choice of characters that he sings about. They often revel in or battle with their own difference, something he has done since he was a child. That outer layer has been replaced, but there is no lesser sense of grandeur or intrigue to the new, more open performer. A generic call to arms for people to throw a little glitter on their differences and celebrate them has been one of pop's most tremendous gifts to music. Mika's come with their own unique darkness this time, too, most notably on the charging melody of "Dr John" and the unhinged dilemma at the centre of the brassily brilliant "Blame It On The Girls."

Because he had got it so spectacularly right first time out by sticking to his guns, there was a personal edict from his label boss not to interfere this time either. 'I have been protected. There was a blockade on interference and I was left completely and utterly alone.' If at first Mika had difficulty coming to terms with the solitude, he over-rode it in the most unusual way. 'Discipline solved it. I went to the studio at 10 o'clock every morning, had my lunch at the same place every day and went to the same pub at 7 o'clock every evening.' Because there is a tendency in Mika to attempt to cover so much ground, it all has to feel like it is shot with the same camera. 'There is an understanding with everyone that I work with that they are in my world only. We don't listen to any other music. We get lost in this world.'

In the process of making his second album, Mika has unleashed something in himself by letting go of something of himself. 'I feel liberated. I've gone to the next place. I needed to do that and I have conquered a process which will help in terms of the third and fourth records. I have finally come to terms with the fact that my little bedroom records aren't bedroom records any more and that I'm a songwriter.'

And a brilliant, brave pop star, to boot.