‘An accident?’ she spluttered.

‘Murder,’ I replied.

I seized her by the arm, allowing the waves to float us away from the trireme. I stared out, but the bank of mist had now thickened. I caught glimpses of distant lights and recalled that the pearl fishermen often came out here at night. I struck out in their direction, Agrippina following. The fishermen already knew something was wrong. As one of their craft, a torch in its prow, came thrusting through the water towards us, we called out. Voices replied. I grasped an oar, making sure Agrippina did likewise and strong burly hands plucked us from the sea.

The oyster men had no idea whom they had picked up, until Agrippina stretched out her hand, displaying the imperial ring. She was nursing a wounded shoulder and a cut to her cheek, but the physical wounds were nothing to those inflicted on her soul. She sat in the boat, a haggard, ageing woman, dripping with sea water, staring sightlessly into the darkness. I bribed the fishermen with some of the coins I still had in a purse stitched to my belt to cross the bay into the Lucrine Lake. They happily agreed, navigating its narrow channel and crossing a sand bar which protected us against pursuit. We landed safely, and, half-carrying Agrippina, I staggered along the beach and up the trackway to her own villa. I aroused the servants, who took one look at Agrippina and knew what had happened. Even as I shouted orders, most of them backed away, owl-eyed, pale-faced, and within the hour most of them had fled. I placed Agrippina in the triclinium and brought metal dishes full of burning charcoal, towels, napkins and heavy military cloaks from the stores. I made her strip off, then dried and changed her before wrapping a blanket round her. I warmed some wine and forced her to drink. The villa fell quiet except for the occasional patter of feet, and the howling of a dog. Agrippina sipped at the wine before being violently sick. I moved her to another part of the room, where we sat on stools.

‘You are still wet,’ she murmured. ‘Dry yourself off.’

I stripped, changed, wrapped one of the blankets round me and rejoined her. Agrippina had now grown more composed. She stared out through the window at the starlit sky.

‘We are creatures of the night, Parmenon,’ she whispered. ‘It’s finished, isn’t it?’

‘It’s always been finished,’ I replied. ‘Ever since Poppea walked into Nero’s court.’

She sighed. ‘They’ll have to complete the job, Parmenon. They won’t let it rest. The slaves and servants have fled. Poor Acerronia.’ A tear trickled down her kohl-smeared cheek. ‘And Creperius, gone with the rest.’ She nudged me. ‘You should flee too. They’ll kill you. They won’t allow any witnesses to survive.’

‘I’ll stay. My life, Domina, is yours.’

She turned, her eyes wrinkled up in a smile, that dazzingly beautiful woman I’d met so many years earlier.

‘You are good, Parmenon.’

She kissed me lightly on the lips and brushed my face with the tip of her finger.

‘If I had listened to you. .’

‘You can still do that,’ I urged. ‘You could flee, seek refuge with the legions.’ My voice faltered.

She pressed a finger against my lips.

‘You and I both know that’s not possible. Every road and trackway will be watched and sealed.’ She put down her wine and stretched her hands towards the charcoal brazier. ‘Isn’t it strange, Parmenon? We first met on the feast of Minerva, at the games in the amphitheatre near the Campus Marius.’

I cradled my own cup. My mind going back. .

‘Sic Habet! Sic Habet! Let him have it! Let him have it!’

The crowd thundered in one great roar, people on their feet leaning forward, thumbs pointing to the ground: the populace of Rome shrieking for a man’s life. I watched the arena, where Sullienus, in Thracian armour, had brought down Callaxtus the net man. The latter hadn’t fought very well; he had been clumsy and frightened, although admittedly, I myself was not the most stalwart of warriors. Although it was early spring the amphitheatre was hot and close. The stench of cooking sausages, oil, human sweat and blood seeped everywhere. Sullienus turned, sword raised towards the imperial box draped in purple and gold. I was sitting at the back. The Emperor was not present: Tiberius was ensconced to Capri, taking his cronies, vices and power with him. Rome was under the careful scrutiny of Sejanus, Prefect of the city, Commander of the Praetorian Guard.

As Caesar’s right hand, Sejanus also controlled the secret police, which is where I come in. My father had died, his remains buried somewhere in the Teuterborg forest, and my mother had not long survived his death, wasting away to skin and bones. Before she died, though, she had hired a scribe and dictated a letter on my behalf to her distant kinsman Sejanus. He hadn’t bothered to meet me himself, but had delegated the task to one of his minions. I had expected a posting in the army, as I had done some military service or, in view of my education, a benefice in the courts or treasury. Instead Sejanus’s minion (I forget his name but remember his face), sat on the corner of a table and scrutinised me carefully.

‘You don’t look Roman.’ He got up and walked round, examining every inch of my close-cropped head. ‘Swarthy, aren’t you? Are you sure you’re Roman? I’d wager you were Numidian or Mauretanian?’

‘I’m Roman. My mother’s family are of Spanish blood.’

‘Ah,’ the Minion replied. ‘I see you can read and write, have done service with the auxilaries and that your father was killed in Germany?’

‘He was a centurion,’ I replied. ‘In the Second Augusta until he was swept up in Varus-’

‘Shush!’ The Minion tapped me on the shoulder. ‘The first lesson of the imperial court is that you never mention Quintilius Varus, his legions, or his defeat.’

He walked away as if still shocked by my utterance. I sat and stared. The Minion was correct. No one wanted to know about Varus, and how he had led his legions into snow-bound forests only to be ambushed. They say the massacre took almost a week as the Germans broke the legions and hunted them down amongst the dark, demon-infested trees. When Germanicus invaded, to reclaim Rome’s honour and its lost eagles, he found the remains of Varus’s armies strewn over miles: bones heaped in glades; skulls nailed to tree trunks; the charred flesh of those burnt on altars or sacrificed in wicker baskets.

‘So, you are a kinsman of Dominus Sejanus. But a very distant one, aren’t you? I’ve done a little research on you, Parmenon. They say you are surly, taciturn, but a good listener. Is that true?’

‘I am listening to what you say,’ I replied.

The Minion laughed at my joke.

‘We need men like you, Parmenon. His excellency Dominus Sejanus needs eyes and ears. Would you be his eyes and ears, Parmenon?’

I knew all about Dominus Sejanus. ‘You mean a spy, an informer?’

I kept my face impassive, but I was angry. I may be many things, but I am no traitor. The Minion was insulting me. His excellency Dominus Sejanus was insulting me but. . I had no family, no prospects, no money. Moreover, if I refused this offer, I had no doubt something rather unpleasant would happen. Men like Sejanus don’t allow you to refuse such a proposal and then walk away.

‘I would be his excellency’s faithful servant,’ I replied and made a secret sign with my fingers, a childish trick to ward off the effect of a lie.

‘Good!’ the Minion exclaimed. He shifted his cloak and sat down behind his desk. It was a tawdry little chamber in an outbuilding of the Palatine Palace. He picked up a piece of parchment.