Lustrum

republic?'

Celer exchanged glances with his cousin. 'I don't know. That depends on what you want me to do.'

'It's dangerous work,' warned Cicero, knowing full well that this would make the challenge irresistible to a man such as Celer.

'I've never been called a coward. Tell me.'

'I want you to take a detachment of your cousin's excellent legionaries, cross the river, climb the Janiculum and haul down the flag.'

Even Celer swayed back on his heels at that, for the lowering of the flag – signalling the approach of an enemy army – would automatically suspend the assembly, and the Janiculum was always heavily protected by guards. Both he and his cousin turned to Lucullus, the senior of the trio, and I watched as that elegant patrician calculated the odds. 'It's a fairly desperate trick, Consul,' he said.

'It is. But if we lose this vote, it will be a disaster for Rome. No consul will ever again be sure he has the authority to suppress an armed rebellion. I don't know why Caesar wishes to set such a precedent, but I do know we can't afford to let him.'

In the end, it was Metellus who said, 'He's right, Lucius. Let's give him the men. Quintus,' he said to Celer, 'are you willing?'

'Of course.'

'Good,' said Cicero. 'The guards should obey you as praetor, but in case they make trouble, I'll send my secretary with you,' and to my dismay he pulled his ring from his finger and pressed it into my hand. 'You're to tell the commander that the consul says an enemy threatens Rome,' he said to me, 'and the flag must be lowered. My ring is the proof that you are my emissary. Do you think you can do that?'

I nodded. What else could I do? Metellus meanwhile was beckoning to the centurion who had weighed in against Catilina, and very soon afterwards I found myself panting along behind a contingent of thirty legionaries, their swords drawn, moving at the double, with Celer and the centurion at their head. Our mission – let us be frank about this – was to disrupt the Roman people in a lawful assembly, and I remember thinking, Never mind Rabirius, this is treason.

We left the Field of Mars and trotted across the Sublician Bridge, over the swollen brown waters of the Tiber, then traversed the flat plain of the Vaticanum, which was filled with the squalid tents and small makeshift huts of the homeless. At the foot of the Janiculum the crows of Juno watched from the bare branches of their sacred grove – such a mass of gnarled black shapes that when we passed and sent them crying into the air it was as if the very wood itself had taken flight. We toiled on up the road to the summit, and never did a hill seem so steep. Even as I write, I can feel again the thump of my heart and the searing of my lungs as I sobbed for breath. The pain in my side was as sharp as a spear tip being pressed into my flesh.

On the ridge of the hill, at the highest point, stands a shrine to Janus, with one face turned to Rome and the other to the open country, and above this, atop a high pole, flew a huge red flag, flapping and cracking in the stiff wind. About twenty legionaries were huddled around two large braziers, and before they could do anything to stop us we had them surrounded.

'Some of you men know me!' shouted Celer. 'I am Quintus Caecilius Metellus Celer – praetor, augur, lately returned from the army of my brother-in-law, Pompey the Great. And this fellow,' he said, gesturing to me, 'comes with the ring of our consul, Cicero. His orders are to lower the flag. Who's in command here?'

'I am,' said a centurion, stepping forward. He was an experienced man of about forty. 'And I don't care whose brother-in-law you are, or what authority you have, that flag stays flying unless an enemy threatens Rome.'

'But an enemy does threaten Rome,' said Celer. 'See!' And he pointed to the countryside west of the city, which was all spread out beneath us. The centurion turned to look, and in a flash, Celer had seized him from behind by his hair and had the edge of his sword at the soldier's throat. 'When I tell you there's an enemy coming,' he hissed, 'there's an enemy coming, understand? And do you know how I know there's an enemy coming, even though you can't see anything?' He gave the man's hair a vicious tug, which made him grunt. 'Because I'm a fucking augur, that's why. Now take down that flag, and sound the alarm.'

Nobody argued after that. One of the sentries unfastened the rope and hauled down the flag, while another picked up his trumpet and blew several piercing blasts. I looked across the river to the Field of Mars and the thousands all standing around there, but the distance was too great to judge immediately what was happening. Only gradually did it become apparent that the crowd was draining away, and that the clouds of dust rising at the edge of the field were being raised by people fleeing to their homes. Cicero described to me afterwards the effect of the trumpet and the realisation that the flag was coming down. Labienus had tried to calm the crowd and assure them it was a trick, but people in a mass are as stupid and easily frightened as a school of fish or a herd of beasts. In no time word spread that the city was about to be attacked. Despite the pleas of Labienus and his fellow tribunes, voting had to be abandoned. Many of the fences of the sheep pens were smashed by the stampeding citizens. The stand where Lucullus and Metellus had been sitting was knocked over and trampled to pieces. There was a fight. A pickpocket was stabbed to death. The pontifex maximus, Metellus Pius, suffered some kind of seizure and had to be rushed back to the city, unconscious. According to Cicero, only one man remained calm, and that was Gaius Rabirius, rocking back and forth on his bench, alone on the deserted platform amid the chaos, his eyes closed, humming to himself some strange and discordant tune.

For a few weeks after the uproar on the Field of Mars it seemed that Cicero had won. Caesar in particular went very quiet, and made no attempt to renew the case against Rabirius. On the contrary: the old man retired to his house in Rome, where he lived on, in a world of his own, entirely unmolested, until a year or so later, when he died. It was the same story with the populists' bill. Cicero's coup in buying off Hybrida had the effect of encouraging other defections, including one of the tribunes, who was bribed by the patricians to switch sides. Blocked in the senate by Cicero's coalition, and threatened with a veto in the popular assembly, Rullus's immense bill, the product of so much labour, was never heard of again.

Quintus was in a great good humour. 'If this were a wrestling match between you and Caesar,' he declared, 'it would all be over. Two falls decide the winner, and you have now laid him out flat twice.'

'Unfortunately,' replied Cicero, 'politics is neither as clean as a wrestling match, nor played according to fixed rules.'

He was absolutely certain that Caesar was up to something, otherwise his inactivity made no sense. But what was it? That was the mystery.

At the end of January, Cicero's first month as president of the senate was completed. Hybrida took over the curule chair and Cicero busied himself with his legal work. His lictors gone, he went down to the forum escorted by a couple of stout fellows from the Order of Knights. Atticus was as good as his word: they stayed close, but not so conspicuously that anyone suspected they were other than the consul's friends. Catilina made no move. Whenever he and Cicero encountered one another, which was inevitable in the cramped conditions of the senate house, he would ostentatiously turn his back. Once I thought I saw him draw his finger across his throat as Cicero passed by, but nobody else seemed to notice. Caesar, needless to say, was all affability, and indeed congratulated Cicero on the power of his speeches and the skill of his tactics. That was a lesson to me. The really successful politician detaches his private self from the insults and reverses of public life, so that it is almost as if they happen to someone else; Caesar had that quality more than any man I ever met.

Then one day came the news that Metellus Pius, the pontifex maximus, had died. It was not entirely a surprise. The old soldier was nearer seventy than sixty and had been ailing for several years. He never regained consciousness after the stroke he suffered on the Field of Mars. His body lay in state in his official residence, the old palace of the kings, and Cicero, as a senior magistrate, took his turn as one of the guard of honour standing watch over the corpse. The funeral was the most elaborate I had ever seen. Propped on his side, as though at a dinner, and dressed in his priestly robes, Pius was carried on a flower-decked litter by eight fellow members of the College of Priests, among them Caesar, Silanus, Catulus and Isauricus. His hair had been combed and pomaded, his leathery skin massaged with oil, his eyes were wide open; he seemed much more alive now that he was dead. His adopted son, Scipio, and his widow, Licinia Minor, walked behind the bier, followed by the Vestal Virgins and the chief priests of the official deities. Then came the chariots bearing the leaders of the Metelli, Celer at the front, and to see the family all together – and to see as well the actors parading behind them in the death masks of Pius's ancestors – was to be reminded that this was still the most powerful political clan in Rome.

The immense cortege passed along the Via Sacra, through the Fabian Arch (which was draped in black for