I had only been away at the manhole for a moment, but I should have been prepared. This was Rome; leave a treasure house unguarded for three seconds and some sneak thief was bound to clamber in.

I had not seen the man's face, though that sense of having recognized him clung persistently. The green hood pulled so securely round his head was unmistakable: the man I had seen while I was emptying the wash bucket. Cursing him, then myself, I limped out to the alley with blood trickling down my leg.

Scattered patches of sunlight threw up a piercing dazzle, while the dense shade was unnervingly cold. The passage at the back of the warehouse was barely three feet wide, with one entrance onto a filthy cut throat lane. The other way, a crook-shouldered curve hid its exit from view. Lining both sides were dank yards crammed with world-weary trolleys and piles of teetering kegs. Dirty ropes snaked into gaping doorways. Ferocious notices hung by a nail warned visitors away from gates that looked as if no one had opened them for ten years. Surveying this sour commercial hole it seemed impossible that a two-minute walk would bring you to the bright bustle of the Forum-this was Rome. As I said.

No one in sight. A pigeon fluttered on a roof then slipped in through a broken pantile. A gantry creaked once. Nothing else moved. Except my heart.

He could be anywhere. As I looked for him in one place, he would slip off another way. While I busied myself searching, he or some quite unconnected evildoer could jump out unexpectedly and bash in my curly head. If so, or if I fell through a rotting floor in one of these deserted stores, I might lie there undetected for days.

I hopped back. I used an old nail to spring back the teeth of the lock on the warehouse door. I checked the sun-baked yard. Using the military pincers Frontinus had brought, I reapplied the gate chains like a responsible person. Then I left.

The smell of the corpse had infiltrated my clothes. Unable to bear it any longer, I went home to change.

I lived in the Thirteenth Sector. In empty streets it took ten minutes, though at this time of day forcing myself through the crowds occupied three times that. The hubbub seemed worse than usual. I reached home feeling deafened and desperate.

The Falco apartment was the best I could afford, so it was grim. I rented a filthy garret above the Eagle Laundry in a street called Fountain Court (which had never possessed a fountain, and wasn't a court). To reach this impressive location I had to turn off the comparative luxury of the paved Ostia Road, then squeeze down a series of twisting entries that grew narrower and more threatening at every step. The point where they diminished into nothing was Fountain Court. I flailed through several lines of damp togas that were blocking the laundry's frontage, then attacked the long haul up six flights of stairs to the sky-high hovel that served as my office and home.

Once aloft I knocked, for the hell of it and to warn off any wildlife frolicking in my absence, then I told myself to come in and unlatched the door.

I had two rooms, each a bare eight foot square. I paid extra for a rocky balcony but my landlord Smaractus allowed me a discount in the form of natural daylight through a hole in the roof (plus free access to water, whenever it rained). There were multimillionaires in Rome who housed their horses better, though thousands of anonymous individuals fared even worse.

My penthouse was for tenants who went out a lot. Yet for five years this squalid hole had seemed gracious enough, especially since when I was running around for clients I was rarely there. It had never been cheap; nowhere in Rome was. Some of my human neighbours were objectionable types, but an amiable gecko had recently taken up residence. I could entertain four people if I opened the door to the balcony, or five when one was a girl who would sit on my lap. I lived alone; financially I had no choice.

Anxious to discard my insanitary tunic, I stepped quickly across my outer room. There I had a table where I ate, wrote, or thought about the filthiness of life, plus a bench, three stools, and a cooking oven I built myself. In the bedroom stood my lopsided bed, alongside a spare couch, a storage chest which doubled as a washstand, and a perch for when I forced myself to patch the leaky roof.

Stripping off with relief, I used the last water in a pitcher for another good scrub down, then found a tunic that had only torn in two new places since the last time my mother mended it. I combed my hair roughly, rolled up my second-best toga in case I went anywhere respectable later, then pounded downstairs.

While I was delivering my castoffs I heard myself hailed raucously by Lenia, the laundress.

'Falco! Smaractus wants your rent!'

'What a surprise! Tell him we can't all get what we want in life…'

I found her in the corner she used as an accounting room, sitting in her greasy slippers while she supped mint tea. Until this pitiful ninny decided to invest in real estate (and real misery) by planning to marry our landlord Smaractus, she had been one of my shabby friends; once I could persuade her to ditch the brute she would be again. Lenia was a sagging drab about five times stronger than she looked, with startling snaggles of henna-red hair which constantly worked free of a limp scarf round her head; she had to poke the strands back in to peer ahead safely when she wanted to go anywhere.

'He means it, Falco!' She had sickly eyes and a voice like forty dried peas rattling in a pannikin.

'Good. I like a man whose ambitions are serious…'

By this time my attention was wandering, as Lenia undoubtedly knew. There was another woman with her whom she introduced as Secunda, a friend. We had long passed the time when I saw any advantage in flirting with Lenia, so I spent a few moments giving the glad eye to her friend.

'Hallo! I'm Didius Falco; I don't believe I've seen you before?' The lady jingled her arm bangles and smiled knowingly.

'Watch him!' Lenia commented.

Secunda was mature without being over ripe; she was old enough to pose an interesting challenge, yet young enough to suggest overcoming the challenge could be very worthwhile. She had a thorough inspection of me, while I gazed back frankly.

I was offered mint tea, but its unappealing grey colour led me to decline on grounds of health. Secunda received my impending departure with fragrant regret; I assumed the expression of a man who might be detained.

'Some ferret-faced scavenger came in for you, Falco,' Lenia scowled.

'A client?'

'How should I know? He had no manners, so he seemed your type. He barged in and asked your name.'

'Then what?'

'He left. I wasn't sorry.'

'But,' Secunda added sweetly, 'he's waiting for you outside, I think.' She missed nothing-if there was a man in it.

Lenia's cubbyhole was open on the street side, except for the clutter of her trade. I tweaked at the laundry until I could look out without being seen. A green cloak with its hood well up was loitering against the open doorflap on Cassius' bread shop two doors down.

'Him in the green?' They nodded. I frowned. 'Some tailor's found himself a gold mine there! Evidently green cloaks with pointed hoods are all the rage this month…' I would soon know; it was my eldest nephew's birthday next Thursday, and if that was the latest fashion Larius was bound to ask for one. 'Has he been there long?'

'He arrived just after you did and has been waiting ever since.'

I felt distinctly apprehensive. I had been hoping that the citizen in green was just an opportunist thief who had noticed something going on at the warehouse and gone in to explore as soon as he thought Frontinus and I had left.