He took a torch from his pocket, and we followed him into a huge cellar. It was built partly into the foundations of the house and partly into the volcanic rock on which it stood. As the torch beam swung around the space, it flashed upon piles of boxes and old-fashioned trunks, bicycle parts, tractor parts, a pile of old plates and dozens of empty glass jars. Tipped on its side was the proscenium arch of an old-fashioned puppet theatre.

My heartbeat quickened. If the missing painting was going to be anywhere, surely it would be here. Joe looked around keenly, his eyes searching, as mine were. Francesco hesitated behind us, at the door.

‘Lotta junk, huh?’ Vito asked, kicking a box. He went beneath a bricked archway, further into the cellar. ‘Mind your heads, folks.’ We followed. Now we were in the service area of the cellar. It smelled of oil. There was a generator, a boiler, some kind of pumping mechanism. ‘There’s a reservoir under the villa that collects the rainwater that runs off the hill,’ Vito explained. ‘This pump here sends it up. You’ll want to boil it before you drink it, but it’ll be good water for bathing; make your hair shine.’ He winked at me. ‘My wife swears by the water that comes off the hills.’ He directed the torch into various nooks and crannies in the complex system. ‘Jesus H Christ, it’s in a terrible state. I don’t know if I’ll be able to do anything with this.’

At the far end of the service area was a second archway. I walked towards it. ‘Can we take a look through here?’

Vito said: ‘Go ahead. Me and Francesco need to get the tools out the truck.’

He tossed the torch to Joe. It was a poor throw and Joe didn’t catch it and the torch rolled towards the foot of the boiler, the beam spinning chaotically, lighting up wires hooked to the roof of the cellar, tools on the walls and, in one high corner, a line of tiny, hanging bats.

Joe picked up the torch and directed the beam towards the far arch. I followed him into the third part of the cellar, vaulted and fitted out from floor to ceiling with wine racks. Most of the racks were empty but, at the far end, were dusty bottles, stacked in rows.

‘How come you didn’t know about the cellar?’ I asked Joe.

‘This was the Ganzarias’ territory. The housekeeper and the caretaker. The family would never have come down here.’

I looked over my shoulder. There was no sign of Vito or Francesco.

‘What if he’s something to do with the mafia too?’ I whispered.

‘Vito?’

‘Yes! He’s Gabriele Arnone’s nephew. Mafia is a family thing, isn’t it? Isn’t that the whole point?’

‘Shhh,’ Joe replied.

‘But what if—’