`Well, he did it.' I noticed her father was as brisk as me. We had both wasted too many hours while woolly arguments were waffled and decisions were avoided; this was pleasingly clear-cut. `The consul asked for a new waterclock to be set -'

`And you all waited? You just waited in the Curia for the next hour to pass?' Helena was still outraged. I patted her arm, trying not to look as if I wished I had thought of the test.

'Rhoemetalces was allowed to sit – he had been standing as he gave evidence of course,' said her father. `So he stayed on a bench, back very straight, with his arms folded. Nobody dared go near him. Except Paccius sometimes.'

`To reassure his client?' Helena scoffed. `The client who might be dying in front of him? At his suggestion?' Decimus inclined his head, acknowledging the filthy ethics. `This is not about the defendants at all, is it? This is purely a battle between Silius and Paccius,' Helena scoffed. `They don't care a quadrans what happens to anybody else.'

The senator spoke levelly. `They have a long-standing feud, yes. Not personal enmity, but a legal tussle for supremacy. While the man sat there, hoping, they even joked together. You could say they respect each other's professional qualities – or you could say it stinks!' He knew Helena's version. I think we all knew his. `The rest of us milled about, people rushed to and from the Forum, the news spread, more crowds gathered outside, everyone muttered in small groups and stared over at the apothecary.'

`And what happened to him?' I was busting to know.

`Nothing happened.'

`He was right about the pills: he lived?'

`So far.'

`He may have a slow digestion,' Julia Justa commented, as if some child in her household was being watched after swallowing a denarius.

`Yes. The consul had him taken under guard to his own house, where he will stay, under surveillance, through tonight. He will be allowed neither food nor drink, lest he take an antidote. If he is alive tomorrow morning -' The senator paused. I did not begrudge him. The story was sensational.

`What do we think will happen?' I asked.

`We think – since he lasted an hour in court and still looked nervously confident – we think Rhoemetalces will survive the night.'

`That's all he needs to do.'

`It is indeed, Marcus. Then the case is over.'

That was how it turned out too. It must have been the easiest defence Paccius Africanus ever came up with. Well, easy for him. For Rhoemetalces, and even for Juliana, it would have been nerve-racking.

The defendants were freed by the consul next morning. Juliana was taken home in procession by her husband and family, amidst what many thought were unseemly signs of triumph. The apothecary, who was unmarried, returned alone to his medicine booth, where for a very short time he attracted a large queue of customers. Notoriety cast its usual sordid spells. He made a fortune that afternoon. Soon, however, people started to remember how he had owned up that he had made money from selling expensive pills which would not work.

This was no more cynical than most lying lozenge-pushers, but when he thought it mattered, Rhoemetalces had been honest. We cannot have that. Rome is a complex, sophisticated society. Truth is distrusted as much as Greek philosophy. So the customers began to stay away.

His trade diminished until Rhoemetalces could no longer earn a living. The Senate had awarded him the most meagre compensation for the court case, because of his low rank. The struggle became too hard. Eventually he took opium poppy sap and killed himself. Few people heard about it. Why should they? He was just the little man who was dragged into the troubles of the great. I seemed to be the only person who commented on the irony of his suicide.

The Metellus troubles, which were deemed so much more exciting, still continued to bubble like an unwatched pot that will thicken and splutter and slowly increase in volume until it boils over. There was bound to be more yet. The praetor had ruled that on the evidence, he could not say the death of Metellus was murder – nor could he decide that it had been an accident. Silius Italicus, an unforgiving informer, still wanted to be paid for the corruption case he won. Now he had been punched in the purse again – having to pay compensation at a senatorial level to Rubiria Juliana for the failed prosecution. Paccius Africanus would benefit from this, but even he wanted to screw yet more fame and money out of the events.

Occasionally someone would remember that if the corn cockle pills had not killed Metellus senior, then something else must have done.

I NEVER CARED for January and February. You might as well be in northern Europe. At least there people have fires in their huts to keep them warm and they don't even try to go out on the streets, pretending to enjoy life.

In Rome it is a period of dark festivals. Their origins are lost in history, their purpose is deeply agricultural or to do with death. I tend to dodge rituals involving seeds and I damn well hate being smeared with blood from sacrificial animals. This unhappy stuff continues until the Caristia – also hideously named the Festival of the Dear Relative. People are supposed to renew family ties and resolve quarrels. Whatever deity thought that up should be locked in a cell with a ghastly brother he hates, while close kin who have offended his most cherished beliefs and stolen his chickens gather round to smile at him lovingly until he runs screaming mad.

Fortunately my family never knows what festival is what, so we don't patch up our tiffs. Much healthier. Our grudges have the historical grandeur most families so sadly lack. Rome is a traditional city; what better way to pursue our national character than by maintaining age-old bitterness and storming out like royalty whenever too many have collected in the same room?

Amongst the offspring of the late Rubirius Metellus, there cannot have been much time for observing festivals. They were always too busy wondering who was being charged with a capital offence that week. If they visited temples, their prayers may well have been fervent, but I bet they went there heavily veiled. Even the ones who were not personally making a sacrifice that day would want to cover their faces to avoid being recognised. In particular, they needed to avoid Silius and Paccius, who must both now be owed money on a flamboyant scale.

Paccius Africanus, it was now rumoured in the Forum, had made a killing with side bets on whether Rhoemetalces would die in the Curia. Yes, gambling is illegal in Rome. There must be a special dispensation for dispensers of the law. (Think of all those gaming boards scratched openly on the steps of the Basilica Julia.) No, I don't know how Paccius got away with it. Shocking. I blame the authorities for turning a blind eye. (In fact, I blame the authorities for receiving hot tips from him.)

Cheered by his winnings, Paccius Africanus took up where Silius Italicus had left off. He charged Metellus Negrinus with bringing about his father's death.

It was not yet public knowledge. I knew. I had been favoured with an urgent request to visit Paccius to talk about the charge.

Unlike Silius, Paccius saw me at his own house. They were opposites in several ways. Silius had ordered me to see him, then did his arrogant best to be invisible. In contrast, Paccius treated me with every courtesy. He even sent a chair with livened bearers. I was bringing the Camilli, but we decided against trying to squeeze in all three of us; they trudged behind. When we arrived, Paccius rushed out at once to greet us in the atrium. The atrium was grand. Black marble and a superb bronze nymph in the pool. He owned a smart home. Well, of course he would.