After a time, Roscius left the Galatea with one of the men he had been talking to. The underling was a fish-faced bag-carrier. We split up to follow them, which is supposed to make you less noticeable. We all played the game of shifting positions, now me at the back, then Faustus, criss-crossing the street with Titianus. Tragic. It fools no one.

The gangsters behaved as all of them do. They sauntered about, making their presence known. Money was picked up at a couple of places for certain. Banter was exchanged. It all looked friendly. That is the evil side of such people. They come around smiling, but their position in the neighbourhood is entirely based on threat.

Roscius picked out an apple at a fruit stall. He paid nothing for it. The stallholder made no attempt to ask him. Roscius strolled on, munching, then threw most of the apple in the gutter. He was just enjoying his power.

I had his measure. That familiar mix of boorish self-belief and ingrained bad manners. From the way he walked – knees apart, arms loose like a bad wrestler – I could see why the vigiles thought he might be aiming high, or was ready to split off by himself if the gang chiefs let him. I bet when he sat in a bar he had a hand in his lap and constantly jiggled his privates, not knowing he was doing it.

I wondered how he got on with Gallo. Gallo looked as if he had been around a long time. His backing could make Roscius a leader, but if he despised the young upstart, Gallo could be the one to thwart him. The fixer’s choice might depend how much talent Roscius really had. To me, he did not look too clever. Not that stupidity holds back career criminals (as my father would say glumly), any more than it hampers promotion in the vigiles, election to the Senate, making a rich marriage, bringing too many children into the world, or being an amateur who buys an ‘ancient Greek’ statue and then sells it on for a fifty per cent profit, despite that new label from a workshop in Capua stuck on the base …

I wondered whether old Rabirius saw his nephew as an asset or a liability.

Then I wondered how healthy Rabirius was. What if he passed away? Could the Esquiline be facing an underworld power struggle? Would Gallo, the hard-man fixer, expect to inherit the business to which he had presumably contributed much? Would he be strong enough to dispose of any challenge from young Roscius, or would the old man nominate family to take over, and disappoint Gallo?

Titianus was gesticulating. Faustus and I caught up with him. ‘They’ve gone in the Dilly-Dally.’