‘If Diogenes is a trader,’ Helena mused, ’he could be involved in all sorts of commerce with numerous people. It doesn’t follow that what he is doing at the Library also involves your uncle.’

‘No, and the sun never sets in the west.’

‘Marcus, we could ask Fulvius about it.’

‘The trouble with Fulvius is that even if he is completely innocent, he will give us a tricky answer on principle. And what am I to do, love, if I find out there is a scam - and a member of my own family is in it? Possibly more than one member.’

‘You are thinking of Cassius?’

‘No,’ I said grimly. ‘I meant Pa.’

All three were out when we arrived home. That saved me having to tackle them.

When they rolled in, we could tell they had all been at a very extended business lunch. We could hear them coming even before they wove unsteadily into the outer courtyard. Crossing it took about half an hour from when they staggered in through the gateway telling the porter that they loved him. All of them were extravagantly good-humoured, but almost incomprehensible. I had given myself the task of interrogating three elderly degenerates who had lost all reason, plus any semblance of manners or bladder control. We would be lucky if none of them suffered a stroke or a heart attack; even more lucky if no irate neighbours came to complain.

What do pensioners do for vandalism? Write graffiti on a Temple of Isis in very neat Greek? Untie a row of donkeys then put them all back in the wrong places? Chase a great-granny up the street, threatening to give her a little kiss if they catch her?

Pa was in the lead. He took a run at the stairs and managed to propel himself as far as the salon. He aimed at a couch, missed, landed face down on a pile of cushions and immediately fell asleep. Helena insisted we turned him on his side lest he suffocate. I poked him hard, just to be sure his sleep was genuine. For me, he could choke.

Fulvius stumbled and fell down as he came up the stairs. This made him even more woozy, and there was a chance he had broken his leg, which had twisted awkwardly beneath him. Cassius spent a long time trying to get Fulvius first to their bedroom and then into, or at least on to, the bed. Fulvius was cursing and being unhelpful. Cassius was cursing back and, I think, weeping mildly. Various household slaves were watching goggle-eyed from doorways, always dodging out of sight the minute anyone invited them to lend assistance. I offered. Either nobody heard me in the kerfuffle, or nobody was capable of taking in what anybody else said.

I removed to the roof with my family. We read Aesop’s Fables to the children. Eventually we ran out of fables and just enjoyed the sun’s last evening rays.

Cassius had been, perhaps, the least intoxicated. Eventually, he joined us up there. He burbled a few apologies, interspersed with momentary snores. Somehow he got himself on to a daybed, while we all watched in silence.

I walked downstairs. Fulvius and Pa were alive, but completely out of it. I rooted out the staff and politely requested a meal for those of us who were able to eat.

Back on the roof, I sized up Cassius and decided he at least could answer questions. ‘Good lunch?’

‘Ex-cell-ent!’ He was so impressed with his enunciation, he continued to say the same thing several times.

‘Yes, I think we can see that.. .Were you with that trader, Diogenes?’

Cassius squinted at me, though he was not in the sun. ‘Diogenes?’ he mumbled Wearily.

‘I heard Fulvius knows him.’

‘Ooh, Marcus . . .’ Cassius was wagging his finger at me, as if he knew even through the drink that I had asked something forbidden. The finger wavered wildly, until he poked himself in the eye. Helena gathered up the children (who were fascinated by the extraordinary adult behaviour) and moved with them to the furthermost part of the roof terrace. Though she could be a disapproving little piece, Albia stayed with me. ’Have to ask Fulvius about that!’ decreed Cassius, when he finished wiping his watering eye on his arm.

‘Yes, I will ... So did Diogenes give Fulvius a good deal then?’

‘Ex-cell-ent!’ answered Cassius. Too late, he realised his mistake.

Albia looked at me and shuddered. She was right. This was dire -the sight of a man in his fifties, hunching up and hiding his face behind his fingers while he giggled at us like a guilty schoolboy.

XLIII

Far be it from me to be self-righteous. The fact was, every generation hates the others to have fun. Human nature makes us deplore bad behaviour in the young - but bad behaviour in the old is just as grim. It was clear I would never get much sense from any of this intoxicated trio that evening, and by tomorrow, if they survived and started to sober up, they were unlikely to remember who they had been entertaining - or who had been entertaining them - let alone what anyone had said or what agreement they shook hands on.

If I could persuade them to back out of the deal, that might be just as well.

The rest of us had a subdued evening, as tends to happen when half a household has had a great adventure and the other half has not. I went to bed early. We all did. The girls were so good, Uncle Fulvius would be sorry to have missed it.

Next morning, Helena and I woke gently, entwined in love but wary about what the day might bring. My family ate breakfast together, Helena and I, our daughters and Albia. There was no sign of our elders. Even if they had begun to come round and realised that a new dawn had broken, daylight would hurt, recollection would be fleeting and troublesome. If they had all come round, they probably decided to keep out of the way until they could compare notes. I had no doubt they would be unrepentant.

Helena said she would take the girls out sightseeing. She would come home after lunch, to check on the debauchees, see if medical attention was required and try to get sense out of them.

‘You are a martyr to goodness.’

‘I am a Roman matron.’

‘She will give them a strong dressing-down,’ suggested Albia, hopefully.

I grinned. ‘You can be there to watch, so you will know how to do it yourself, one day.’

‘I shall avoid sharing my house with wicked old men, Marcus Didius.’

‘Don’t say that. You never know what Fortune will dump on you.’

‘I can handle Fortune. Are you going to see Aulus?’

‘If Aulus is where I am going, I shall see him, certainly’

‘You have to make a riddle out of everything.’

‘So where exactly are you going, Marcus?’ put in Helena.

I told her I was starting at the Library. This business with the scrolls seemed the most profitable line to pursue. The episode with the crocodile seemed unconnected, probably just a domestic tiff gone hideously wrong. I said I expected to be home early, hoping to grill Fulvius and Pa about their involvement with Diogenes. But a lot was about to happen before I made good that promise.

Helena thought events could be turning nasty; she wanted me to take a sword. I refused that, but I sharpened my knife to please her.

As I left the house, the muttering man leapt to his feet but I passed by him with an angry face and left him trailing. He dogged my footsteps, but I kept going. I stared ahead, and although for a while I fancied he had stayed behind me, by the time I reached the Museion I saw no more of him.

Pastous was in the Library, but not Aulus.

‘Have you finished up?’

‘Yes, Falco. There was nothing more of interest among the documents. In among the last batch we sorted, we found this.’ He held up an object. ‘It is the key to the Librarian’s room.’

The lock had now been replaced but the diligent Pastous had rooted out the broken one. The key was portable, though heavy - made of brass, with a sphinx decoration. I tried it. Despite the damage to the lock, it turned in both directions. According to the assistant, Theon had found the key too cumbersome to carry about with him except when he left the building. When he was in attendance at the Library, he hung it outside the room on a discreet hook.