‘I’ve got a philosophical question,’ I said. ‘Do you realise that your continually lying to me is an erosion of trust that could have adverse consequences at a later date – for instance in about five minutes?’

‘Not really,’ said Zach around a mouthful of chips. ‘I’ve always been a live-in-the-moment kind of guy. A grasshopper not an ant. What happens in five minutes?’

‘I finish my tea,’ I said.

If you live in London just about the last thing you expect is a white Christmas. The stallholder had been ready for the festive season. There was tinsel draped around the struts of his stall and a small plastic Christmas tree with a ‘Last Minute Xmas Bargains!’ sign attached where the fairy should go. But he had to keep knocking the accumulated snow off his awning or risk it collapsing. It also meant he was much more pleased to see me than he might have been – even after seeing my warrant card.

‘My brother, my brother, my brother,’ he said. ‘I know the law never sleeps, but surely you must be looking for something for someone special.’

‘I’m looking for an earthenware fruit bowl,’ I said and showed him a picture on my phone.

‘I remember these,’ he said. ‘The man who sold them said they were unbreakable.’

‘Were they?’

‘Unbreakable? As far as I know.’ The stallholder blew on his hands and then stuffed them into his armpits. ‘He said it was an ancient process whose secrets had been guarded since the dawn of time. But it looked like pottery to me.’

‘Who’d you get them from?’

‘It was one of the Nolan brothers,’ he said. ‘The youngest – Kevin.’

‘Who are the Nolans?’

The stallholder looked at Zach. ‘You know them, Zachy boy, don’t you?’ he said.

Zach bobbed his head noncommittally.

‘Nolan and Sons wholesalers,’ said the stallholders. ‘Only strictly speaking they’re the Nolan Bros. now since the dad died.’

‘Local boys?’

‘Not for ages,’ he said gesturing vaguely south. ‘Covent Garden now.’

I thanked him and gave him a tenner for his trouble. It never hurts to cultivate, and I was thinking that wherever the case went, Portobello needed to be on my radar. I wondered when was the last time Nightingale had been up here – probably not since the 1940s.

‘If you don’t need me anymore,’ said Zach. ‘I’ll be off.’

‘Not a chance,’ I said. ‘You can come with me down to Covent Garden.’

Zach twisted up his shoulders. ‘What do you need me for?’

Because you don’t want to go, I thought, and because you’ve marked enough squares on the suspicious behaviour board for me to call bingo.

‘You can be my local guide,’ I said.