My apartment was high in a vast, ramshackle block. A laundry occupied all the space at street level; woollen tunics awaiting collection were the only things in our neighbourhood that were clean. Once on, their pristine condition could be ruined by one short trip down the muddy single track that served as both our exit road and the nearest we had to a sewer, amidst the smuts from the lampblack furnace where a one-eyed stationers' supplier brewed stinking domestic ink, and the smoke from the beehive ovens where Cassius our local bread-man could char a loaf to the verge of destruction like no other baker in Rome.

These were dangerous byways: in a moment of lapsed concentration, I sank to the ankle in sticky brown dung. While I was muttering and cleaning my boot on a kerbstone, Lenia the laundress stuck her head round a line of tunics. Seeing me, she bustled out to deride me as usual. She was an ill-kempt bundle who approached with the gracelessness of a swan landing on water: wild writhings of luridly dyed red hair, watery eyes, and a voice that was hoarse from too many flagons of badly fermented wine.

'Falco! Where've you been all week?'

'Out of town.'

It was unclear whether she knew I meant in the Lautumiae. Not that Lenia would care. She was too lazy to be curious, except in closely defined areas of business. Those included whether my filthy landlord Smaractus was being paid his dues - and she only became really curious about that after she decided to marry him. A decision made for purely financial reasons (because Smaractus was as rich as Crassus after decades of squeezing the Aventine poor) and now Lenia was preparing for her wedding with the clinical will of a surgeon. (Knowing that the patient would pay heavily for her services, after she had carved him up...)

'I gather I'm in credit,' I grinned.

'You finally found out how to pick a woman!'

'True; I rely on the Parian perfection of my face-'

Lenia, who was a harsh critic of the fine arts, cackled cynically. 'Falco, you're a cheap fake!'

'Not me -I come with a certificate of quality from a lady of good repute! She likes to pamper me. Well I deserve it, of course... How much has she contributed?'

I could see Lenia opening her mouth to lie about it; then she worked out that Helena Justina was bound to tell me, if ever I had the good manners to discuss my debt. 'Three months, Falco.'

'Jupiter!' That was a shock to my system. The most I ever reckoned to donate to my landlord's retirement fund was three weeks (in arrears). 'Smaractus must think he's been transported on a rainbow to Olympus!'

I deduced from a certain cloudiness in Lenia's expression that Smaractus had yet to discover his luck. She changed the subject rapidly: 'Someone keeps coming here asking for you.'

'Client?' Nervously I wondered if the Chief Spy had already discovered me missing. 'Take his details?'

'Oh I've better things to do, Falco! He turns up every day and every day I tell him you're not here-' I relaxed. Anacrites would have had no reason to be looking for me until this afternoon.

'Well, I'm back now!' I felt too weary to be bothered with mysteries.

I set off up the stairs. I lived on the sixth floor, the cheapest of all. It gave me plenty of time to remember the familiar smell of urine and old cabbage ends; the stale pigeon droppings staining every step; the wall graffiti, not all of them at child height, of stickmen charioteers; the curses against betting agents and the pornographic advertisements. I knew hardly any of my fellow tenants, but I recognised their voices quarrelling as I passed. Some doors were permanently closed with oppressive secrecy; other families opted for no more than curtained entrances which forced their neighbours to share their dismal lives. A naked toddler ran out of one, saw me, and rushed back inside screaming. A demented old lady on the third floor always sat in her doorway and gabbled after anyone who came by; I saluted her with a gracious gesture which set her off into torrents of venomous abuse.

I needed practice; I was stumbling when I finally reached the top of the building. For a moment I listened: professional habit. Then I operated my simple latch-lifter and pushed open the door.

Home. The sort of apartment where you go in; change your tunic; read your friends' messages; then find any excuse to rush straight back out again. But today I could not face the nightmares on the stairs a second time, so I stayed in.

Four strides permitted me to survey my premises: the office with a cheap bench and table, then the bedroom with a lopsided contraption that served as my bed. Both rooms had the worrying neatness that resulted when my mother had enjoyed three days of uninterrupted tidying. I looked around suspiciously but I reckoned no one else had been there. Then I set about making the place my own again. I soon managed to knock the sparse furniture askew, rumple the bedclothes, spill water everywhere as I revived my balcony foliage, and drop all the clothes I had been wearing onto the floor.

After that I felt better. Now it was Home.

Prominent on the table, where not even I could miss it, stood a ceramic Greek bowl which I had bought off an antiques stall for two coppers and a cheeky smile; it was half full of scratched bone counters, some with extremely odd streaks of colour. I chortled. The last time I saw these was at a ghastly family party where my little niece Marcia had seized them to play with and swallowed most of them: my betting tags.

When a child has eaten something you prefer not to lose, there is only one way- if you are fond of the child- to recover it. I knew the disgusting procedure from the time my brother Festus swallowed our mother's wedding ring and pressured me to help him find it. (Until he was killed in Judaea, which put an end to my fraternal duties, there was a tradition in our family that Festus was the one who was always in trouble, while I was the fool he always persuaded to dig him out of it.) Gulping down family valuables must be an inherited trait; I had just spent three days in prison wishing constipation on my feckless brother's sweet but feckless child...

No need to worry. Some hard-headed relation- my sister Maia probably, the only one who could organise - had gallantly retrieved these tags. To celebrate, I pulled up a floorboard where I had half a wine jar hidden away from visitors and sat out on my balcony with my feet up on the parapet while I applied all my attention to a restorative drink.

As soon as I was comfortable, a visitor arrived.

I heard him come in, gasping for air after the long climb. I kept quiet, but he found me anyway. He pushed through the folding door and accosted me chirpily. 'You Falco?'

'Could be.'

He had arms as thin as pea-sticks. A triangular face came down to a point at a dot of a chin. Above it ran a narrow black moustache, almost ear to ear. The moustache was what you noticed. It bisected a face that was too old for his adolescent body, as if he were a refugee from a province racked by twenty years of famine and tribal strife. The true cause was nothing so dramatic. He was just a slave.

'Who's asking?' I prompted. By then I had warmed up enough in the late-afternoon sunshine not to care.

'A runabout from the house of Hortensius Novus.'

He had a faintly foreign accent, but it lay a long way back behind the common lilt all prisoners of war seem to contract in the slave market. I guessed he had picked up his Latin as a small child; probably by now he could hardly remember his native tongue. His eyes were blue; he looked like a Celt to me.

'You have a name?'

'Hyacinthus!'

He said it with a level stare that dared me to scoff. If he was a slave he had enough problems without enduring ribaldry from every new acquaintance just because some overseer with a filthy hangover had stuck him with the name of a Greek flower.