Maximian himself, their former master, would not be joining them. He alone had been granted mercy by his son-in-law. Nigrinus had seen the old man, his tunic ripped at the neck in shame, kneel before the emperor’s horse and plead forgiveness. And forgiveness had been given, of course. Even Constantine, it seemed, could not order the death of a man who had been one of the two supreme emperors of the world, a man who had stood beside the gods.
Now the prisoners were being made to kneel, each man forced to his knees with a rough hand at the back of his neck. The execution party was formed of eight tough-looking horse-guard troopers of the Schola Scutariorum. They would be paid a good bonus for this duty, and were going about it in a brisk efficient manner.
Nigrinus was standing with the other spectators, a gathering of military officers and civilian dignitaries, in the shade of the portico that circled the courtyard. He tried to keep his eyes on the condemned men and their executioners, although he was aware, despite his play-acting in the torture dungeon beneath Arelate, that he was still not inured to the sight of bloodshed. He had no pity for the men. Only hours before he had been released from a prison cell himself, perhaps the same one that had later held Gorgonius and his comrades. He had been lucky. Being found in captivity had preserved his life; that, and the information he had already been able to give about the usurper’s court and military affairs, and his connections with his son in Italy.
But Nigrinus knew how close he had come to disaster. A different throw of the dice, and he could be kneeling with the prisoners in the courtyard. Still, he felt a sour sense of disappointment. Flaccianus’s sudden treachery had robbed Nigrinus of the chance to arrange the surrender of the city to Constantine. In the end, of course, the citizens themselves had done it, led by a few renegade soldiers. All his months of slow steady planning had come to nothing. Or, Nigrinus thought, almost nothing. He had escaped with his life when he could so easily have lost it; now only one brutish soldier still knew the depth and extent of Nigrinus’s deceptions. He wondered if he should rid himself of Aurelius Castus. It could certainly be done. But, then, the soldier’s unwitting dalliance with the emperor’s wife was still a secret. That was a weapon that Nigrinus could use against him, if in his stupidity he ever dared to mention what he knew.
Down in the courtyard the optio of the execution party was swinging his long cruel blade. One of the prisoners – the civilian, Macrobius – retched and spat on the gravel. Nigrinus felt the pulse jumping in his neck. There was a flutter deep in his stomach, a sensation of combined repulsion and excitement. It was, he was embarrassed to note, almost a sexual feeling. He had a strong desire to wash his hands.
The sword flashed up, then dropped, and Nigrinus closed his eyes at the last moment. A sharp exhalation came from the spectators in the colonnade, and when Nigrinus looked again he saw the eunuch’s body sagging sideways, his severed head lying in a spreading lake of blood. Now the soldier moved on to Gaudentius. A swish and a thump, and the second head fell. Nigrinus forced himself to keep watching. It was fascinating, he decided. Swish, thump. Macrobius died, then Diadumenus. Four bodies slumped like sacks of grain. Four heads lying on the bloody gravel.
‘It must please you to see this,’ a voice said. Nigrinus turned, startled, and found Probinus standing beside him. The Praetorian Prefect rocked back on his heels, pursing his lips.
‘Justice enacted is always a pleasure, dominus,’ Nigrinus said.
‘Indeed.’
But now another figure was approaching along the colonnade. Nigrinus bowed his head and saluted his chief, Aurelius Zeno, Primicerius of the Corps of Notaries. Zeno bobbed his shaved skull in response, giving Nigrinus a sideways smile.
‘I’m glad to see you free once more!’ he declared. ‘I look forward to hearing a full report of all you learned after infiltrating the usurper’s court. A very full and confidential report, of course!’
Nigrinus bowed his head again, inhaling slowly as his chief turned to walk away. There was a pressure in his chest. He lifted his head and addressed the Praetorian Prefect.
‘Unfortunately, dominus,’ he said, ‘the most highly placed member of Maximian’s treasonous conspiracy has yet to be brought to justice.’
The prefect gazed at him, raising an eyebrow.
‘Oh? His name?’
‘His name, dominus…’ Nigrinus felt his mouth grow suddenly tight and dry. He swallowed, then raised his voice slightly. ‘His name is Aurelius Zeno.’
The chief of the Corps of Notaries stopped mid-pace. He began to turn, began to smile, but a look of sick panic was flickering in his eyes. ‘Surely you don’t think…’ he began to say.
‘He was organising the murder of our emperor Constantine,’ Nigrinus declared. ‘He intended to strike on the third day of the siege. I have documentary proof.’
Zeno let out a low groaning cry and turned sharply, beginning to run towards the far end of the colonnade, his shoes skidding and slipping on the smooth marble floor. But Probinus raised his arm, calling an order, and two guardsmen appeared to block the fugitive’s way, hands on the hilts of their swords.
Turning again, Zeno glanced quickly into the courtyard: the slumped corpses, the pooling blood, the executioners standing ready. He was breathing hard, biting his lips. Then, with one motion, he drew a short dagger from his belt, reversed the blade and plunged it into his sternum. He fell forward onto his knees, then collapsed onto the polished floor as the guards closed around him.
‘Interesting,’ said Probinus with a sniff. ‘How did you know?’
‘Nearly a year ago,’ Nigrinus told him, ‘Aurelius Zeno ordered me to investigate the correspondence of Maximian’s intimates.’ He was shaking as he spoke, but his voice was steady. Just for a moment, he had felt death’s black wing brush against him.
‘Zeno intended,’ he went on, ‘that I should report to him if I found anything suspicious. It was an insurance policy, I believe. If I found evidence of treason, he would know that his communications network had been compromised. And I would be signing my own death warrant, of course. However, he did not know that I was also investigating his own correspondence.’
‘How very… thorough,’ the prefect said. He stiffened his shoulders and drew away from Nigrinus slightly.
‘Yes. And when I discovered in one particular concealed message a reference to Zeno himself, I realised the nature of the game. Instead of reporting it, I travelled south and pretended to Maximian’s people that I was Zeno’s intimate and fellow conspirator. They accepted me amongst them, and I was able to fully examine all their correspondence from then on.’
‘Ingenious,’ Probinus said with something like a sneer. He took another step away from the notary. ‘It occurs to me,’ he said, ‘that there now exists a vacancy a the head of your department.’
‘I suppose there does.’
Probinus sniffed again. ‘Perhaps you will be hearing from us shortly, then,’ he said.
Nigrinus glanced away to hide his blush of pleasure. He tried to form the correct words, the phrases of polite gratitude that protocol demanded. But the prefect was already striding away from him with his hands clasped behind his back.
All the other officials gathered under the colonnade also seemed to have moved away from Nigrinus, and he stood alone, gazing down into the courtyard.
It matters nothing, he thought. Soon they will have cause to hate me more. Soon they will have cause to fear me. His thin lips tightened into a smile. The rich metallic stink of fresh blood was in the air, and it no longer made him feel queasy. No, he thought; it smells very much like triumph.