Oplontis was a way station on the road to Herculaneum. It was not far, though more than anybody wanted to tramp after a day of lugging lead to and fro. Pompeii was sited on rising ground (an ancient lava field I suppose, though we had no reason to guess that then); as we turned north in the warm twilight a complete panorama of the shore confronted us. We stopped.

It was almost July. The nights grew dark without ever growing old. It was dusk now, with the steep cone of Vesuvius just vanishing from view. All along the beautiful Bay, from Surrentum to Neapolis, where the tycoons of Campania and various important Romans had built their seaside villas over the past fifty years, twinkled the lanterns that lit their fanciful porticos and romantic colonnades. At this time of year most were in residence. The entire sweep of the coastline was dotted with dancing yellow lights from bonfires on the beach.

'Very picturesque!' Larius commented wryly. I had paused for breath, allowing myself a moment of enrapturement. 'Uncle Marcus, this seems a good chance to have our embarrassing chat. "Larius"' he mimicked, '"why does your daft mother say you're being difficult?"'

He was half my age and twice as despondent but when he stopped being miserable he had a wonderful sense of fun. I was very fond of Larius.

'Well, why does she?' I grunted, irritated at being interrupted in a fit of reverie.

'No idea.' In the second it took me to bring out the helpful question he had reverted to being a morose lout.

While my nephew gazed at the scenery, I scrutinized him.

He had an intelligent brow under an unkempt swath of hair that drooped into solemn, deep brown eyes. Since I saw him throwing nuts at his little brothers last Saturnalia he must have shot up three digits in height. His body had stretched so fast it had left his brain trailing behind. His feet, and ears, and the parts he was suddenly too shy to talk about, were those of a man half a foot taller than me. While he was expanding into them, Larius had convinced himself he looked ridiculous; in all honesty he did. And he might fill out handsomely-or he might not. My Great-uncle Scaro looked like a listing amphora with out-of-proportion jug handles all his life.

In view of his surly answer, I decided a man-to-lad talk would be unprofitable tonight. We started to walk again but after another ten paces, he heaved a dramatic sigh and fetched out, 'Let's get it over with; I promise to cooperate!'

'Oh thanks!' I was trapped. Casting round in despair I asked him conventionally, 'What does your schoolmaster think of you?'

'Not much.'

'That's a good sign!' I heard his head turn doubtfully. 'So what's causing your mother all this grief?'

'Didn't she tell you?'

'She was well-primed for a torrent but I didn't have three days to spare. Tell me yourself

We must have marched on for half a minute. 'She caught me reading poetry,' he admitted in the end.

'Good gods!' I burst out laughing. 'What was it-rude verses from Catullus? Men with big noses, vindictive whores in the Forum, grubby lovers chomping at each other's private parts? Believe me, there's more pleasure, and much better nourishment, in a decent lunch of goat's cheese and bread rolls…' Larius shuffled. 'Your mother may have a point,' I murmured more kindly. 'The only person Galla knows who scribbles elegies in notebooks is her peculiar brother Marcus; he's always in trouble, short of cash, and usually has some scantily clad rope dancer in tow… She's right, Larius: forget poetry. It's just as disreputable, but much more remunerative, to sell green-tinted love potions or become an architect!'

'Or be an informer?' Larius jibed.

'No; being an informer rarely brings in cash!'

Out in the Bay other faint lights were bobbing, as the night fishermen uncovered their lamps to lure their catch. Much nearer at hand a single ship had appeared unnoticed while we walked; she must have come from the direction of Surrentum, hidden in the twilight as she hugged the shore below the Lactarii Mountains, but now she emerged proudly into the centre of the Bay. We could just make her out. She was much smaller than the Circe, altogether a different craft from Pertinax's huge merchantman. This was the sort of toy every rich man who owned a villa at Baiae kept tied up to his landing stage-like the other pleasure boat I had in my life at the moment, the one the conspirator Crispus had fled aboard so conveniently.

Larius and I both slowed our steps. Gliding in silence the ship made a lovely, slightly melancholy sight. We watched, enthralled, as this slender vision crossed the Bay-no doubt some plump young barrister proud of his senatorial ancestors was bringing home a dozen high-class girls with low-grade morals from a beach party on the Positanum coast; his expensive caique was sliding gracefully with a silver wake back towards one of his coastal properties…

My nephew exclaimed with a thrill of speculation he could hardly keep in, 'I wonder if that's the Isis Africana?'

'And what,' I asked him levelly, 'is the Isis Africana?'

And still bursting with the prospect, Larius piped up: 'She belongs to that man Aufidius Crispus. It's the name of the yacht you're looking for…'

We quickened our pace again, our eyes still following the boat, but it grew darker and she was lost from us out in the Bay.

'Very clever!' I scoffed. 'I owe this to your tar-stained nark on the quayside, I presume?' Larius ignored me. I tried to contain my anger. 'Larius, we ought to have tipped him a denarius to stop him warning the owner that we asked.' We kept striding on. I made an attempt to restore peace. 'I apologize. Tell me I'm an ungrateful, bad-tempered swine.'

'You're a swine… It's just his age; he'll grow out of it!' Larius announced to the ocean balefully.

I laughed, ruffling his hair.

'Being a private informer,' I confided, twenty paces later, 'is less glamorous than you think-it's not all hard knocks and easy women, but mostly bad dinners and ruining your feet!' Fresh air and exercise were doing the boy good, but I felt glum.

'What shall we do when we find her, Uncle Marcus?' he fetched out unexpectedly. I had no idea what had brought us back on friendly terms.

'The Isis Africana? I shall have to decide my tactics when I've had a quiet look. But this Crispus sounds tricky-'

'What's tricky about him?'

'Big ideas.' I had done my homework before I left Rome. 'The illustrious Lucius Aufidius Crispus is a senator from Latium. He owns estates at Fregellae, Fundi, Norba, Formiae, Tarracina-good growing land in famous areas-plus a huge villa at the Sinuessa spa where he can sit in the sun and tot up his accounts. In his career in public service he landed jobs in all the wrong provinces: Noricum, for heaven's sake! You've been to school; where's Noricum?'

'Go up to the alps and turn right?'

'Could well be-anyway, when Nero died and Rome came up for auction, nobody had heard of Noricum and nobody had heard of him. Despite that, Crispus sees imperial purple in his horoscope. What would be tricky is if he persuaded Fregellae, Fundi, Norba, Formiae and Tarracina to glimpse it too.'

'Local boy making good?'

'Right! So he's dangerous, Larius. Your mother will never forgive me if I let you become involved.'

Disgust silenced him briefly, but he was too inquisitive to sulk for long. 'Uncle Marcus, you always called politics a fool's game-'

'It is! But I was tired of helping bad-tempered women divorce feeble stationers' clerks, and working for the clerks was even worse; they always wanted to pay me in bottom-grade papyrus you wouldn't use to scribble a curse. Then I was invited to drudge for the Palatine. At least if the Emperor honours his commitments, there should be good pickings.'