HOW does a clinically shy' Asian boy - who used to run upstairs and hide when guests arrived - evolve into a star of the cult series Still Game?

And how does someone who would rather die than speak in public metamorphose into the deliverer of some killer lines?

In the new series of Still Game, shopkeeper Navid confronts a local druggie who has the cheek to complain about her chocolate bar being melted, and suggests Navid should invest in a chiller cabinet.

"That's a great idea," he counters. "We could put your methadone in there as well and keep it nice and cool for you."

Amazingly, given his performing powers, the actor behind the long grey beard, 36-year-old Sanjeev Kohli, maintains no part of him ever screamed out to become a performer.

"Not at all," he says. "I was the shyest of my three siblings. I've always lived in my brother Hardeep's shadow (Hardeep is a comedy writer/ performer, and a frequent guest on a whole range of TV shows)."

Sanjeev wasn't quite the young boy in hit movie East Is East who refused to be removed from his parka - but he wasn't that far removed.

And growing up an Asian-Indian-Scottish boy in Bishopbriggs - his parents came from the Punjab in the mid-60s - added to a sense of alienation.

"I felt this a bit," he says. "I went to a school (St Aloysius - his parents liked the role religion played in the everyday routine) and there were only three non-Catholics there.

"I had my Asian pals I'd see on Sundays at the Sikh temple and during the week was the time for my white pals.

"So it was odd. But I didn't seem to be into the same things as the Asian boys, my cousins. I didn't like bhangra or Hindi films. In fact, me and my brothers were into heavy metal and Led Zeppelin."

At times he had to contend with racist abuse.

"When I was 11 or 12 and I went into town from our house in Bishopbriggs, I was surprised if I wasn't called a name, Little Black Sambo' or Paki' or whatever."

Whether or not comedy has emerged from conflict, Sanjeev Kohli is a very funny bloke. And not afraid to enter the arena of political controversy.

Chatting in Dumfries, where he is on a holiday with wife Fiona and their three kids, he says: "It's lovely and quiet down here. There are no Asians on fire at all."

But as a teenager Sanjeev had yet to realise he could be funny. "I used to sit at the back of the maths class because I couldn't integrate," he says, deadpan.

"Once I wrote a speech that got laughs and then the English teacher asked me if I wanted to join the debating society, but I said, No thanks, my brother Hardeep does all that sort of stuff'.

"I thought I loved being in the shadows."

Girls never entered his shadowy world.

"How could they?" he says, rhetorically. "My school was all boys. And I grew up in a house full of boys."

His face remains as straight as the lined-up tins of soup on Navid's shelf as he adds: "And my mum was one of the first females in Scotland to have the full transgender operation."

Somewhat more seriously, he says: "No, I was really shy with women. I didn't know how to talk to women without them thinking that I fancied them.

"And the reality was, it was only half the time I fancied them."

His first girlfriend came along at the age of 19.

"Don't ask me when I lost my virginity cos I'm not telling you."

He adds, his face still deadpan. "In truth it hasn't happened yet. I bought all of my three kids on the internet."

Sanjeev's inhibition period continued right through to university - where he studied medicine and then maths.

"It's the one degree that required no formalised communication whatsoever," he explains, grinning.

But he was very good at it, picking up a first class honours and going on to do post-grad study at the University of London.

Then a new world of possibility emerged when an old university colleague, Uzma Mir, kicked off a multicultural magazine show for BBC radio. Sanjeev was asked to join in.

"I said to her, But you know I did a maths degree?' Regardless, she asked me to voice test. And I said Sure, it's your funeral'.

"But I tested and got the job - and suddenly I was presenting a radio programme. I guess I needed the validation. And I guess I was literate in that genre."

Sanjeev saw the light that was television. He went on to write comedy, for the likes of Goodness Gracious Me and Chewin' The Fat.

But he admits he had concerns when asked to join the Still Game comedy team. And he expected some sort of backlash from the Asian community - which didn't arrive.

"I didn't know Ford and Greg wanted me to play Navid, I thought they wanted me to keep them right with the cultural references. But it turns out that Ford had heard me impersonating my dad, and thought it would be perfect for Navid."

HE continues: "Yes, I had concerns about stereotyping - until I read the scripts. Then I realised that Navid is real.

"He's cheeky, he's sarky because he's had to develop a ned shield. He has this aggressive get the equaliser in first and the I couldn't give a s*** attitude Glaswegians have.

"It doesn't matter that he has a long beard. He's integrated culturally."

Sanjeev adds, his delivery perfect: "But at the same time he's not setting fire to his daughter's boyfriend and there's been no mercy killings."

Navid's best cutting line? When Isa reveals she wants to go on Stars In Your Eyes as Patsy Cline. But Navid takes the mickey brilliantly.

"Oh yes. Tonight, Matthew, I'll be a bag of kittens drowning in a canal."

In the new series Navid has to take on the supermarket giants. And he gets the chance to put them straight. Sanjeev has no fear for the real corner shops.

"They will always be king," he says, the former shy boy coming up with the killer line: "So long as there is a wooden bat and ball and a sh**ty water pistol to be sold." Still Game, Thursday, at 10pm on BBC2.