Pass Elvis Costello in the street and you wouldn't give him a second glance. A thin, weedy young man with horn-rimmed glasses whose taste in clothes appears non-existent.
But, soon, he will be recognised as the rock star of 1977.
A few weeks ago, he was pushing buttons as a computer operator.
Now, his debut album, My Aim Is True, released little more than a fortnight ago, has already reached No. 14 in the charts.
His concerts in London are sell-outs. At last Sunday's gig at the Nashville, 700 fans were locked out.
The night he opened at Dingwalls, he was arrested (and later fined £5) for singing outside the Hilton Hotel. "We wanted to wake up CBS Records, who were holding their conference there to tell them we had this concert," said Elvis.
That night, Dingwalls was packed.
Elvis is not, of course, his real name. But he won't say what that is. "It has nothing to do with any particular liking for Presley," he says. "When people say 'Elvis isn't very original' I reply, 'Neither is John'."
He is equally reticent about his background, saying only that he was born in Paddington, London, 22 years ago and that his father was a musician.
He does admit, however, that music has dominated his life since he was two, when he first heard a Sinatra version of "I've Got You Under My Skin."
He is at pains to emphasise his normality. "I had an undistinguished career at school — somewhere in the middle of the class.
"When I was 16, my family moved to Liverpool, but I came back to London three years later.
"I was writing music then, but the question always on my mind was — how could I afford it? I mean, if you've an allowance from wealthy parents, that's fine.
"With me, I had to find a job."
He looks too young for it, but he's married to his school sweetheart, Mary, and has a two-year-old son.
He writes earthy, dynamic songs, usually when he's angry. He says: "The singles market has been dull and boring for a long time. The charts are full of garbage and I'm hoping to change things a bit."
It's been a long time since Britain produced a new young musical personality. Stiff Records, who hold Elvis's contract, say he's the hottest property since "The Pelvis" himself.