true. She had known me since my bachelor days. `But I never thought you'd be caught out in the old way!'

It was my turn to say mind your own business, and Lenia's to laugh seditiously.

I changed the subject. `Does your slimy betrothed still own that decrepit property across the court?'

`Smaractus never disposes of a freehold.' He never bothered to redevelop a wrecked tenement either. As an entrepreneur, Smaractus was as dynamic as a slug. `Which property, Falco?'

`The first-floor spread. What's he call it? "Refined and commodious self-contained apartment at generous rent; sure to be snapped up." You with me?'

`The dump he's been advertising on my wall for the past four years? Don't be the fool who does snap it up, Falco. The refined and commodious back section has no floor.'

`So what? My shack upstairs hardly has a roof. I'm used to deprivation. Mind if I take a look at the place?'.

`Do what you like,' sniffed Lenia. `What you see is all there is. He won't do it up for you. He's short of loose change.'

`Of course. He's getting married!' I grinned. `Old Smaractus must be spending every day of the week burying his money bags in very deep holes in faraway fields in Latium. If he's got any sense, he'll then lose the map.'

I could tell Lenia was on the verge of advising me to jump down the Great Sewer and close the manhole after me, but we were interrupted by a more than usually off-putting messenger.

It was a grubby little girl of about seven years, with large feet and a very small nose. She had a scowling expression that I immediately recognised as similar to my own. She was one of my nieces. I could not remember which niece, though she definitely came from the Didius tribe. She looked like my sister Galla's offspring. They 'had a truly useless father, and apart from the eldest, who had sensibly left home, they were a pitiful, struggling crew. Someone had hung one of those bull's-testicle amulets around this one's neck to protect her from harm, though whoever it was had not bothered to teach her to leave her scabs alone or to wipe her nose.

`Oh Juno,' rasped Lenia. `Take her out of here, Falco. My customers will think they'll catch something.'

`Go away,' I greeted the niece convivially.

`Uncle Marcus! Have you brought us any presents?'

`No.' I had done, because all my sisters' children were in sore need of a devoted, uncomplicated uncle to ruin their characters with ridiculous largesse. I couldn't spoil only the clean and polite ones, though I had no intention of letting the other little brats think me an easy touch. Anyone who came and asked for their ceramic Syrian camel with the nodding head would have to wait a week for it.

`Oh Uncle Marcus!' I felt like a heel, as she intended.

'Cut the grizzling. Listen, what's your name -'

'Tertulla,' she supplied, without taking offence.

`What are you after, Tertulla?'

`Grandpa sent me.'

`Termites! You haven't found me then.'

`It's urgent, Uncle Marcus!'

`Not as urgent as scratching your elbow – I'm off!'

`He said you'd give me a copper for finding you.'

`Well he's wrong.' Needing to argue more strongly, I had to resort to blackmail. `Listen, wasn't yesterday the Ides?' One good thing about helping Petronius at Ostia was that we had missed the Festival of the October Horse – once a savage carnival and horse race, now just a complete mess in the streets. It was also the end of the official school holidays. `Shouldn't you be starting school now? Why are you loose today?'

`I don't want to go.'

'Tertulla, everyone who has a chance to go to school should be grateful for the privilege.' What an insufferable prig. `Leave me alone, or I'm telling your grandma you've bunked off.'

My mother was helping with the fees for Galla's children, a pure waste of money. Ma would have stood, for a better, return gambling on chariot races. What nobody seemed to have noticed was that since I gave my mother financial support, it was my cash being flung away.

`Oh Uncle Marcus, don't!'

`Oh nuts. I'm going to.'

I was already feeling gloomy. From the first moment Tertulla mentioned my father I had begun to suspect today might not be all I had been planning. Goodbye baths; goodbye swank at the Forum.. `Grandpa's in trouble. Your friend Petronius told him to get you,' my niece cried. Persistence ran in the family, if it involved telling bad news.

Petro knew what I felt about my father. If Pa was in such trouble Petro reckoned even I would help him out, the trouble must really be serious.

THE EMPORIUM IS a long, secure building close to the Tiber. The barges that creep up from Ostia reach the city with Caesar's Gardens on their left, and a segment of the Aventine district, below the Hill, to their right. Where they meet the lefthand city boundary at the Transtiberina, with a long view upriver towards the Probus Bridge, they find the Emporium lying to their right, a vast indoor market that includes the ancient Aemilian Portico. You can smell it from the water. A blind man would know he had arrived.

Here, anything buildable, wearable or edible that is produced in any province of the Empire comes to be unloaded at the teeming wharves. The slick stevedores, who are renowned for their filthy tempers and flash off-duty clothing, then crash the goods on to handcarts, dump them in baskets, or wheel about with great sacks on their shoulders, ferrying them inside the greatest indoor market in the world. Cynical sales are conducted, and before the importer has realised he has been rooked by the most devious middlemen in Europe, everything whirls out again to destinations in workshops, warehouses, country estates or private homes. The moneychangers wear happy smiles all day.

Apart from a few commodities like grain, paper and spices, which are so precious or are sold in such quantities that they have their own markets elsewhere, you can buy anything at the Emporium. Through his profession, my father was well known there. He no longer involved himself in general sales, for his interest had narrowed to the kind of fine-art trade that is conducted in quieter, highly tasteful surroundings where the purchaser submits to a more leisurely screwing and then pays a more gigantic premium to the auctioneer.

Pa was a character people noticed. Normally I could have asked anybody if they had seen Geminus, and pretty soon someone would have told me which hot-wine stall he was lurking at. I should have been able to find him easily – if only the fierce patrolmen of the Fourth Cohort of vigiles had been letting people in.

The scene was incredible. Nothing like it could ever have happened before. The Emporium lay in the area included by, Augustus when he redrew Rome's boundaries because habitation had expanded. I had made the mistake of coming out from the old part through the city walls, using the Lavernal Gate – a spot always busy but today, almost impassable. Down in the shadow of the Aventine approaching the Tiber, I had found chaos. It had taken me an hour to force a passage through the people who were clogging up the Ostia Road. By the time I really made it to the wharves beside the river, I knew something highly peculiar must have gone wrong. I was prepared for a scene – though not one evidently caused by my sensible friend Petronius.

It was midmorning. The gates to the Emporium, normally closed at night for security but flung open at first light and kept that way well into the evening, now stood barred. Red-faced members of the watch were drawn up with their backs to the doors. There were a lot of them: five hundred men formed the half-cohort that patrolled the river side of the Aventine. A proportion were dedicated to fire-watching, and with the special dangers of darkness they were mostly on duty at night. That still left ample cover to combat daylight crime. Now, Petronius must have drawn up all the day roster. The line was holding, but I was glad I was not part of it. A huge, angry crowd was milling about insulting the watch and calling for Petro's head. Occasionally a group rushed forwards, and the line of patrolmen had to link arms and face them out. I could see a small cluster, at the far end of the building where Porcius was handing out shields from a waggon.