‘Ah, well,’ he said, ‘good first day of the month, to you!’ His accent see-sawed with a Germanic twang. He dropped the cigarette and shook my hand.

‘But it’s the seventeenth already,’ Baaz replied.

‘Rosh Chodesh Sh’vat,’ the man said, before I could apologize for Baaz’s interruption. ‘The first day of the month of Sh’vat of the year 5778.’

‘My, uh, colleague,’ I explained. ‘Bhavneet Singh.’

‘You can call me “Baaz”, though,’ Baaz piped up. ‘Everyone else does. Even my auntie. And she’s super-formal.’

He looked at Baaz, and then back to me.

‘And you can call me di Farreter,’ he said with a grin. ‘Everyone does. Even my auntie. She’s even more formal. Trust me.’

‘What does that mean?’ Baaz asked.

‘It’s Yiddish,’ the man said. ‘It means the Traitor.’

Baaz stepped closer. The child backed away and then scuttled off deeper into the room behind, no doubt spooked by the bizarre goyim at his door.

‘My youngest grandson,’ he explained, still holding my hand, though no longer shaking it. And then, by way of proper introduction: ‘Moshe. Moshe Mendel Katz. At your service.’

‘It’s good to meet you, Mr Katz.’ I stepped a fraction closer; my right hand still clasped in his. ‘You were highly recommended.’

‘Yes, well …’ He let go of my hand and stepped back into the room behind him, opening the wide metal door enough for Baaz and I to follow. ‘Please, close it behind you. Now, where’s the switch?’

We stood in darkness for a moment and then Moshe hit the lights. Out of the darkness emerged an extraordinary storeroom. Piled up in vertical stacks, on the floor, on shelves, in boxes and free standing in bunches of fives or tens rested dozens, hundreds of oil paintings. And above them, hanging properly, fully displayed canvases. Rembrandt. Dali. Turner. Klimt. Anything and everything. The face of Jesus beamed down from the far wall. Above us, Judith beheaded Holofernes. A white, eighteenth-century horse stood in a wide green field. I looked down. Narcissus fell into his own reflection at my feet. I guessed the room may once have been a garage. But now it resembled the overflow from the National Gallery and Hermitage combined.

‘Wow.’ Baaz blinked at the art around him. ‘This is totally cool.’

We both took in the scene. It was as if an art avalanche had poured through the building and stopped at our toes. Baaz stepped towards a canvas of a burning candle and raised his hand, index finger outstretched, as if to touch it.

‘Not that one,’ Moshe cautioned him, urgently. And then, more relaxed, ‘It’s not dry yet.’ Baaz dropped his hand and stared at it intently. I stared at Moshe, reappraising him. It wasn’t egg on his waistcoat. It was yellow paint. And whether this was a shop or a studio, it most certainly wasn’t legit.