In our one previous case together, we had both enjoyed the way the magistrate tried to play the stern monitor and I kicked against it. Now I stared him in the eye until eventually he ducked his head like a submissive dog, allowing himself a tight smile.

I told him he ought to smile more often. ‘It makes you look rather appetising.’ He tried to ignore that, though he came close to blushing. The man was fun to tease, although I suspected no one else ever did it. He had been unmarried for years and from the little I knew about the uncle he lived with, his only visible family, Tullius was not the type.

Of course he was entitled to progress reports. It was a routine part of my service. ‘Daily’ might be pushing it, but I was not foolish; until we apprehended the killer, I wanted somebody else to be aware of my movements. Faustus knew it would not give him supervision rights.

Or maybe he thought it did. He would soon learn.

The long stroll over from the Aventine confirmed that Rome really is built on Seven Hills, and they are highly inconvenient. Three, the Quirinal, Viminal and Esquiline, are steep ridges that run down in parallel and dominate the northern part of the city, getting in your way whenever you try moving about. Most easterly is the Esquiline, which lies mainly outside an ancient fortification, the so-called Servian Walls; the rampart overlooks an area that was once unhealthy and full of graveyards, though now some parts have been reclaimed and fancied up. People who think themselves quite grand nestle alongside workshops with unneighbourly trades and the destitute.

On the city side of the old embankment lurks Nero’s Golden House, a madman’s playground that once covered the Forum and beyond. Down at the bottom of the Esquiline stands the Temple of Minerva Medica. Up at the top is the Market of Livia, named after the Empress who also built an elegant Porticus in this region, full of fountains and an enormous vine that covered all the walls. Livia’s Market is by the Esquiline Gate, where the main road that runs under the arch arrives from the once-rough district called the Subura.

On this road, the Clivus Suburanus, Faustus and I found the Aviola apartment. It took us several tries, asking where Aviola lived, so he was not well-known in the district. Faustus played things unobtrusively but when I despaired of his approach, I walked into a bar and mentioned the robbery and deaths; all the gossipy waiters rushed to point out the crime scene.