Silius could not hold his gaze and lowered his head. ‘Forgive me, commander. I did not want-’

‘Never mind. You know I trust you. I haven’t told you anything because I don’t want to expose you to unnecessary risk. There’s a certain tension in the air. There are. . signs. . clues that something is about to happen. The wait is agonizing and I can’t take it any longer. Maybe that’s why my illness comes upon me so suddenly, when I least expect it. I’ve experienced many things in my life, but I must say that there’s an advantage to being on the battlefield. You know exactly where the enemy stands.’

Silius nodded and watched as Caesar turned his attention back to Pollio’s letter, making notes on his tablet as he read. It seemed that months had passed since his early-morning crisis. Caesar was in perfect control of the situation, but he was tense, worried, and Silius couldn’t help him because he did not know what was upsetting him.

Caesar raised his head again and looked straight into Silius’s eyes. ‘Did you know that last year, when I was in Spain, there were strange rumours circulating in the rear lines?’

‘What rumours, commander?’ asked Silius. ‘What are you referring to?’

‘Just rumours,’ replied Caesar. ‘Pass me those papers to be signed. I’ll read the letters later.’

Romae, a.d. VIII Id. Mart., hora sexta

Rome, 8 March, eleven a.m.

Strange rumours.

The expression nagged at him and Caesar’s words kept ringing in his ears. Silius tried to remember what had happened in those rear lines. . because he had been there, in Marseilles, in Narbonne, organizing logistics, communications.

It had been a bloody campaign, perhaps the worst ever. Titus Labienus had been there then, at Munda. Labienus, who had been Caesar’s right-hand man, the hero of the Gallic War, his second in command. Willing to take on any responsibility, to face any danger, never tired, never dispirited, never doubting. An old-fashioned Roman, a principled man, an officer with a formidable temperament.

He had been at the head of the enemy formation at Munda, where the fight had been to the death.

Labienus had deserted his commander when Caesar had decided to cross the Rubicon and enter the territory of the republic — a land considered sacred and inviolable — with weapons in his hand. He had gone over to the side of Pompey and his sons, to the side of those who had proclaimed themselves defenders of the republic, the Senate and the people.

At Munda the clash had been of inconceivable savagery. The combatants on both sides fought with unrelenting fury and, at a certain point, it had seemed to Silius that their adversaries (despite everything that had happened, he still couldn’t force himself to think of those men as enemies) would prevail. It was then that Caesar had been prepared to take his own life. He knew that, if he lost, there could be no mercy for him, and he was convinced that, as an aristocrat, suicide was the only honourable way of ending one’s life in the event of defeat.

But then the unimaginable happened. Labienus withdrew one of his units from the right wing of the formation with a view of reinforcing the left wing, which was under constant pressure, but his men had all instantly feared a retreat and panicked, abandoning their combat positions in a disorderly fashion. The battle ended in a massacre. Thirty thousand adversaries dead.

Were those the visions that ravaged Caesar’s mind? Was the memory of such horror the trigger behind the seizures that were crippling him?

But Caesar’s words seemed to be referring to something different: rumours circulating in the rear lines, strange rumours, obviously upsetting. What could he mean?

Who should he ask? Publius Sextius, perhaps, the man Caesar trusted most. But the centurion was far away, part of some highly sensitive mission. No one knew when he’d be back. Silius thought of another man who might be able to help, a person who had always been close to Caesar but who also maintained relations with many people in the city. Someone he could arrange to meet without difficulty. Silius walked towards the vegetable market, and from there to the Temple of Aesculapius on the Tiber Island. He knew Antistius would be there.

He found him examining a patient with a dry, irritable cough.

‘Has something happened?’ the doctor asked immediately.

‘No,’ replied Silius. ‘The situation is stable. I’ve come to speak to you about something, if I may.’

‘Are you in a hurry?’

‘Not really, but I don’t want to stay away for too long, given the situation.’

‘Sit down in that little office there and I’ll be with you soon.’

Silius entered the office and went to sit near the window. A couple of maniples of the Ninth Legion were stationed on the island and he could see the soldiers coming and going outside. They were carrying dispatches and duty orders to and from the bridges that connected the island to the mainland. Several people got out of a boat which had just docked, evidently coming from the sea.

Antistius’s voice startled him: ‘Here I am. What can I do for you? Is it about your health?’

‘No, not mine. An hour ago I was speaking with the commander and he mentioned something strange.’

‘What were you talking about?’

‘I had taken him his correspondence and some administrative papers that needed signing and he came out with a phrase that had no connection at all to what we were doing. I could tell it was something that was troubling him.’

‘What exactly did he say?’ asked Antistius.

‘Something like: “Do you remember last year, when we were in Spain, the strange rumours that were circulating in the rear lines?” As if the thought had been gnawing at him since then. It was his tone that struck me.’

‘What did you answer?’

‘I didn’t know what to say, and anyway he changed the subject and asked me to give him the documents to be signed. But I thought that you might be aware of something. You were in the rear lines yourself back then, in Narbonne, weren’t you?’

Antistius went to close the door that he’d left open and then sat down. He was silent for a few moments and, when he began talking again, his voice was low, almost a whisper. ‘A doctor in the rear lines of a large military expedition finds himself meeting lots of people, listening to cries of pain, to cursings and ravings, to the confessions of dying men. Men desperate to free themselves of remorse before embarking on that great journey from which no one has ever returned.’

Silius watched him intently. So Caesar’s words had real significance for him.

‘It’s true,’ Antistius continued, ‘that after Caesar’s victory at Munda there was talk of a conspiracy.’

‘A conspiracy? What kind of conspiracy?’

‘Against Caesar. A plot to bring him down. Or worse.’

‘Wait. Explain that more clearly, please,’ said Silius. ‘Just what are you saying?’

‘Our own men, I’m afraid. Highly ranked officers, former magistrates.’

‘I don’t understand. . If you knew these things, why didn’t you tell him? Why didn’t you give him their names? You know their names, don’t you?’

Antistius sighed. ‘They were just rumours. . You can’t condemn a man to death on the basis of a rumour. You can never rule out slander — perhaps lies were being circulated deliberately to ruin someone. Anyway, I’m sure he was just as aware of those rumours as I was. I’ve heard him say the same things he said to you today.’

‘Well, then, why doesn’t he crush them? Destroy them?’

‘Why? Only he knows. If you want my opinion, I think it’s because he believes so strongly in what he did and in what he’s doing. He believes unquestioning in his — how can I say this? — his historical mission. To end the season of civil wars. Establish a period of reconciliation. Put a stop to the bloodshed.’