Claudia always found Rome at twilight a fascinating place, that time between night and day when the Citizens of the Light returned to their garrets, houses or apartments and the Citizens of the Dark came to life! They were all gathering to greet the night. The prostitutes, faces painted, balding heads covered in garish wigs, clustered like a collection of multicoloured butterflies on the corners of alleyways or the entrances to decaying houses and apartment blocks. Sharp-eyed pimps were touting for business. Hawkers and traders were setting up their stalls, most of their goods being the plunder from robberies or what other markets had rejected. Cooks were firing their portable stoves and grills, shouting what they had to sell, most of which was grilled or roasted until it was burned and the putrid taste hidden under cheap sauces and spices. Second-hand clothes-sellers hung their products from the branches of trees, whilst the money-changers, the receivers of stolen goods, lurked deep in the shadows advertising their presence with a tinkling bell. A small boy ran up with a cage of yellow birds; another tried to pester them with purses made out of snakeskin. Claudia just ignored them. She kept thinking of those abductions. Whoever organised the gang would draw their recruits from a place like this, a shifting population of former soldiers, outlaws, tricksters, rejects, slaves on the run, desperate men and women who'd sell their souls for a cup of wine and kill without a qualm for a silver coin.

The deeper into the city they walked, the busier the crowds became. Here and there a squad of auxiliaries or a group of Vigiles squatted outside the door of some tavern keeping an eye on what was happening, though they were more prepared to take a bribe and look the other way than do anything. Of course people recognised Murranus and greeted him with good-natured abuse and catcalls, which the gladiator just ignored.

'I wish…' Claudia paused at the corner of the alleyway leading down to the Lucia Gloriosa tavern.

'What do you wish?' Murranus bent down to hear above the sound of a line of clattering carts.

'I wish I'd questioned Theodore more closely.'

Murranus just squeezed her hand. 'Oh, don't worry about him,' he reassured. 'Theodore will make himself at home. He'll relax and tomorrow it will be all the easier to question him.'

Claudia agreed and walked on towards the Lucia Gloriosa, a fine, spacious eating-house and wine shop, in many ways very similar to the She Asses tavern. The owner, a former soldier, explained that there were no chambers upstairs, only a long, high-ceilinged room into which he ushered them. The chamber's pink plaster walls were unadorned except for hanging baskets of woven reeds and the occasional coloured cloth. The veterans were already assembled, grouped at one end of a trestle table in the middle of which stood a small portable Lares, its doors open to display a statue of some god, a figure on a rearing horse. The statue looked old. Fashioned out of bronze, it had already turned slightly green, the metal starting to flake. Before the statue glowed two small oil lamps placed either side of a loaf of bread, a bunch of grapes and a jug of wine. The three men were busy, heads together, talking amongst themselves. At first they ignored the new arrivals, then Murranus coughed and the three men drew apart.

'What do you want?' The large, burly-faced man sitting at the end of the table spread out his hands and stared at them aggressively. 'Who do you think you are coming up here? Don't you know?' He glared at the tavern-keeper, who was still standing in the doorway.

'I think you'd better explain,' Murranus whispered.

Claudia undid her cloak, laid it on the end of the table and came forward, hands extended. 'My name is Claudia,' she declared. 'I have been sent by the Empress Helena; she wishes me to investigate the deaths of your two comrades.'

'You? Investigate?' One of the men sniggered and turned away.

'You had better listen to me,' Claudia retorted. 'Two of your comrades have been killed: a cut to the belly, their throats sliced and then castrated.' She paused. 'I am Claudia, agent of the Empress. I carry her bulla, her seal. Shall I call up a squad of Vigiles or those mercenaries lounging in the nearby market, then we can go to the palace so all this can be verified? Oh, by the way.' Claudia noticed how the veterans had shifted their attention to her escort. 'This is Murranus, Victor Ludorum – Champion of the Games, but also a freedman.'

The veterans relaxed. They waved the newcomers to the bench, found two more cups and filled each with a measure of water and wine.

As Claudia and Murranus settled at the table, the veterans introduced themselves as Stathylus, Crispus and Secundus; their Latin names belied both their appearance and their accents, which clearly showed them to be provincials. They acted full of confidence, old soldiers who'd seen all the horrors of war and could not be surprised by anything new. Claudia had met their kind before: leathery-skinned, sharp-featured, still wiry despite the folds of fat round the belly and face. They were dressed simply in tunics, belts and sandals. She noticed the war belts heaped in the corner as well as the cudgels and walking sticks lying on top of their cloaks. They were friendly enough, explaining how they met here regularly to share bread and wine and toast former comrades, recall long-forgotten battles and pay homage to their guardian Epona, horse goddess of the Iceni, a tribe which lived along the eastern coastline of Britain. They revelled in their former membership of the Fretenses, and were proud to be called the Vigiles Muri.

Claudia let them chatter on as the wine flowed. Stathylus, sitting at the top of the table, had been a junior officer, a decurion. He was hard-faced, with close-set eyes; he remained both watchful and hostile, aware of what Claudia was doing. Now and again he'd urge his two companions to drink slower or mix more water in their wine cups. Claudia, however, gently encouraged them to discuss their earlier careers, and of course, like all old soldiers, they were only too willing to talk. They were all Iceni horsemen from the flat plains of eastern Britain. Horse-lovers, born cavalrymen, they described how they'd been recruited into the Catephracti, the heavily armed cavalry, and been given various postings in that faraway, mist-shrouded province. Eventually they'd been posted to a mile fort along the Great Wall Emperor Hadrian had built in the north, stretching from coast to coast to seal off the province from the wild tribes beyond. They'd fought under a veteran centurion, Postulus, but during the civil wars, mutinies and the emergence of pretenders such as Allectus and Carausius, their numbers had been depleted. They were proud of having fought for Constantine Chlorus, the present Emperor's father, and of supporting the cause of Helena and her son through all their difficulties. They had as a unit been honourably discharged and given the opportunity to settle outside Rome. Some had brought their wives and families; others had simply deserted their roots for a new future at the heart of the Empire.

Secundus and Crispus did most of the talking. Born storytellers, they described their service in Britain, conjuring up images of deep forests, lonely wind-swept moorlands, freezing winters when all was carpeted in snow, followed by springs bursting with light and summers which brought the brilliant green grasslands and cornfields to life. They talked of warm breezes, a golden sun and rain-washed blue skies. Above all they described the Great Wall. Many of the tribes regarded this as the work of the gods with its soaring crenellated wall, watchtowers, signal posts, mile castles and great five-mile fortresses. The two men described the boredom of military life, offset by the terrors which lay beyond the wall, where savage Picts and Caledonians, superb fighters, slipped like wraiths through the tangled heather to probe, attack and ambush. The savagery and cunning of these tribesmen was something they had never forgotten, a terrifying nightmare constantly lurking just beyond the Roman line, ever vigilant, ruthless and merciless. Claudia listened fascinated, aware of the day dying, the darkness deepening, the flames of the oil lamps growing stronger. She became less aware of the peppery, spicy odour of the room, with its wisps of black smoke, whilst every time she looked at the carving of Epona, it seemed more lifelike. She noticed, however, that all three veterans deliberately skirted the crowning glory of their careers, the ambush and annihilation of that Pictish war band. At last