The stallholder was a dwarf broad bean who had been left on life's vine until he turned leathery in the pod. He let out a yowk that attracted attention from three streets away. A tight crowd assembled, penning me against the stall. Elbowing forwards came some local layabouts whose idea of a good market day was beating up an unarmed priest. Under my tunic I had a safe-conduct signed by Vespasian, but down here they probably had not even heard yet that Nero had stabbed himself. Besides, my passport was in Latin which seemed unlikely to fill these shanty town bullies with respect.

I could not move because of the crowd. I assumed a haughty expression and pulled my religious veiling more securely over my head. I apologized to the herbseller in my best formal Greek. He jabbered more wildly. Stumpy Crotonese joined in. This was clearly the sort of friendly southern marketplace where peasants with shiny expressions and two left ears were just looking for a chance to set upon a stranger and accuse him of stealing his own cloak.

The rumpus was growing uglier. If I jumped over the stall they would grab me from behind, a cheap thrill I preferred to avoid. I kicked up one heel behind me to investigate the stall; it was just a trestle covered with cloth, so I dropped to the ground, gathered up my priestly garments, and scuttled under like a reclusive rat.

I came out between two piles of conical baskets, with my nose against the stallholder's knees. He seemed deaf to reason, so I bit him on the shin. He hopped back, shrieking; I scrambled out.

I now had one rickety table between me and a premature funeral. One glance at the multitude convinced me I really needed my little phallus amulet against the evil eye. (A gift from my sister Maia; so embarrassing I had left it at home.) The crowd swayed; the table lurched, then I crashed my hip so it toppled over towards the Crotonese. As they all jumped back I held up both hands in prayer.

'O Hermes Trismegistos-' (I'll pause here to mention that since I had been bound to tell my mother I was leaving Rome, the only divinity who might be watching my progress was Hermes the Thrice Great in his role as the patron of travellers, who must have been having his ear bent painfully by my ma.) 'Aid me, wing-footed one!' (If things were quiet on Mount Olympus he might be pleased to have an errand here.) 'Offer the protection of your sacred caduceus to a fellow messenger!'

I stopped. I hoped curiosity might encourage the bystanders to leave me alive. If not, it would take more than a loan of a winged sandal to hop free of this predicament.

No sign of young Hermes and his snaky staff. But there was a puzzled lull, another surge, then out of the surge leapt a bronzed, barefooted man in a curly-brimmed hat who vaulted the trestle straight at me. I was unarmed of course; I was a priest. He was flourishing a monstrous knife.

Yet I was safe. In a trice this apparition had his weapon at the liquorice merchant's throat. The blade was twinkling sharp-the sort sailors keep for slicing through dangerous tangles of rope on shipboard or murdering each other while they enjoy a drink ashore. He was more or less sober, but gave the impression that cutting out the lives of people who looked at him too closely was the way he relaxed.

He bawled at the crowd, 'One step closer, and I stick the herbalist!'

Then to me: 'Stranger-run for your life!'

Clutching swathes of my religious get-up, I hared past the courthouse without stopping to enquire if the magistrate would hear my case. Before the third dark alley I heard my rescuer's bare feet pattering behind.

'Thanks!' I gasped out. 'Well met. You seem a handy type!'

'What had you done?'

'I've no idea.'

'Usual story!' he exclaimed.

We took the road out of town and soon afterwards were sitting in an eating house on the shore. He recommended the shellfish pottage with saffron sauce.

'A melange of shellfish,' I commented cautiously, 'at a tavern with no nameboard, in a strange port, is a risk my mother taught me to avoid! What else do they do?'

'Shellfish pottage-without the saffron!'

He grinned. He had a perfectly straight nose which was attached to his face at an unfortunate angle of thirty degrees. His left side had the uptwitched eyebrow of a bright, comical fellow, and his right the down-jerked mouth of a moody clown. Both halves of his face were fairly presentable; he just lost ground on the composite effect. His two profiles were so different I felt compelled to stare at him, as though he were deformed.

We both ordered pottage, with. Life's short enough anyway. May as well drink deep and die in style.

I paid for a flagon while my new friend called up side dishes; a trug of bread, a saucer of olives, hard-boiled eggs, lettuce salad, whitebait, sunflower seeds, gherkins, slices of cold sausage, and so on. Having fixed a few nibbles, we introduced ourselves.

'Laesus.'

'Falco.'

'Captain of the Sea Scorpion, out of Tarentum. I used to do the Alexandria run, but I gave it up for shorter hops with fewer storms. I'm in Croton to meet someone.'

'I've ridden down from Rome. Arrived today.'

'What brings you to Bruttium?'

'Whatever it was, it now looks like a bad mistake!'

We raised our cups and tackled the hors-d'oeuvres. 'You never mentioned what you do, Falco.'

'Quite right.' I broke off some bread from a circular loaf, then concentrated on cleaning an olive stone between my front teeth. 'I never mentioned it!'

I spat out the stone. I was not so discourteous as to keep secrets from a fellow who had saved my life; Laesus knew I was teasing. We pretended to let it drop.

The place we had come to was surprisingly busy for midafternoon. Seafront canteens are often like that, catering for sailors who have no idea of time. Some customers were drinking at the counter indoors but most were packed onto benches in the open air, like us patiently waiting for their food.

I told Laesus that in my experience quayside tavernas are like that too; you sit for hours imagining they are filleting a fresh-caught red mullet just for you. The real truth is: the cook is a lackadaisical noddy who has disappeared on some errand for his brother-in-law; on his way back he quarrels with a girl he owes money to, then stops to see a dogfight before helping along a game of soldiers at a rival restaurant. He arrives in a filthy temper half-way through the afternoon, warms up a sickly bumper-fish in yesterday's rascasse broth and hurls in some mussels which he can't be bothered to clean, then an hour later you heave up your dinner into the harbour because you drank far too much while you were waiting for the cook…

'Console yourself, Laesus: a meal on a quayside never stays around long enough to poison you!'

He just smiled. Sailors get used to listening to strangers' fantasies.