Sometimes we exchanged a glance, confirming that some character in the street who had looked like our subject was not him. Once I acknowledged how much the latest murder had depressed me, my mind cleared, so I slipped more happily into sharing our task. We had a good working relationship and Tiberius seemed content to be here. ‘Could be worse,’ he commented.

I agreed quietly, ‘One of those times when you wish it wasn’t work.’

He smiled, raising his cup in a mild salute to me again.

Almost at once I saw him stiffen. He gestured slightly with one forefinger.

‘He’s coming! − Shit, we’ll lose him again, he’ll see us …’ It had to be presumed that when Roscius spotted Titianus tailing him earlier, he had noticed us as well.

As Tiberius nodded down the street, I moved. I swung round in front of him like a girl who cared nothing about her reputation. With a shameless lunge, I came in close and hid my companion from where Roscius must be. Tiberius gave a nervous start, then he went with the act, playing a tipsy opportunist as he grabbed hold of me. My stole began to slide off my hair, but he noticed and pegged it. His flattened palm felt strong against my head.

We held the pose, so close our breaths intermingled. I watched his grey eyes following the suspect. There was absolutely no need to embellish our charade, but suddenly he leaned in and kissed me.

As he did it, he was watching. Roscius must have gone in somewhere, but Tiberius continued. He was an unexpectedly good kisser. I liked his faint disconcertion because he was enjoying it more than he had been ready for … Classic male surprise.

When he released me, he flashed a quick gleam, all the recognition he would give or I would want; after all, we were play-acting for work. ‘He’s in the Three-tailed Dog.’

‘Looks a dump!’ I slid back into my seat, feeling warm. I could act suave, however. ‘We know him now. He’ll buy a drink, gulp it quickly, leave half in the beaker then go for a pee out the back. He’ll shunt down the alley and saunter out through one of the other bars.’

‘You’re good.’

‘You too!’ I remarked ambiguously.

I was watching as many bars opposite as I could. Tiberius spent a moment watching me, then he too reapplied himself to surveillance.

I glanced back at him. He steadily scrutinised the exit from the Victorious Soldier and the public counters of the Moon and Stars. I resumed my careful watch on the Ship, the Castor and Pollux, the Cow and the Dead Man’s Fingers.