‘I am so knocked out by this that I start bending the music towards me, sort of, and he smiles. Then I bend it away from me, and he gives a big grin. And once I have started I can’t go back to the way I was. It completely changes how I play. And that was fine until that old witch Miss Southgate goes whingeing to my mam that I’m messing about in her lessons, won’t play the proper tempo. So I have to develop a split style – one to please my teacher and my examiners, and a private way for me and Mr K. At the competition last night, I got carried away and showed too much of my private way – which is why you’ve got me telling you now all about thirty-two Canning Street.’

He repeats the address ghoulishly as if it is a scene of crime, a place of notoriety. The boy looks pale, drained by confession and consumption. Sweat is beading between his acne spots. He sneaks a glance at my expression, keen to see if I am satisfied. My colour has risen, my nostrils are aflare. I am closing in for the kill. Ordering a fresh pot of tea, I resume the interrogation.

‘Did you, Peter, ever ask Mr, er, Katzenberg how he knows so much, how he arrived at his particular philosophy of playing? After all, it scarcely befits the rather secluded life he leads.’

‘Lots of times I asked him, Mr Simmonds,’ says Peter. ‘At first, he changed the subject. Then, when I nagged, he said, yes, he once studied under a great master, Professor Flesch, but he never had the urge to make a career. “You have to want it more than anything on earth,” is how he put it. “More than love, more than money, more than faith, more than life itself. Myself –” he said – “I never wanted it that much.” ’

I am now so close to home that my metabolism begins to shut down, slowing and cooling my reactions to protect the weakened aorta – or so I imagine. Whatever is going on inside my chest, my brain is receiving and processing information with deadly clarity. A strategy starts to form. I am now convinced that Dovidl is still alive, and not far from here. What I do next will determine the rest of his life, and mine. ‘Did you believe that?’ I asked Peter.

‘Sort of,’ says the boy, no fool. ‘I looked up Professor Flesch in Grove’s Dictionary in the reference section at the public library, and there is a list of all his successful pupils, but none by the name of Katzenberg. So I reckon he must have dropped out before he made a début, though I don’t get it.