'Obviously, it was a mistake for me to allow any of the slaves to go on serving Gelina. As soon as the dinner is finished and the overnight guests are seen to their quarters, I shall have every slave rounded up and locked into the annexe. It would have to be done in the morning, anyway. Fabius!' He called to Faustus Fabius, who had been waiting in the hall, and issued instructions. Fabius nodded coolly and left the room without even looking at me.

I shook my head wearily. 'Why do you think it was one of the slaves who poisoned Dionysius, Marcus Crassus?'

'Who else had access to the kitchens, where no one would notice? I suppose that's where Dionysius kept his herbs.'

'All sorts of people have been in and out of the kitchens all day. People were half-starved from waiting for dinner; guests dropped by to filch food or sent slaves to do it for them long before the meal began; the kitchen slaves were rushing about and could hardly be expected to take note of everyone who stepped in their way. And you're mistaken, Crassus; Dionysius gathered his herbs himself and kept them in his room. He sent fresh batches down to the kitchens to be prepared each day; he usually bundled them up first thing in the morning and gave them to a kitchen slave, but today he didn't deliver them until after the funeral. That means the herbs could have been tampered with in Dionysius's room this morning, while everyone was busy preparing for the funeral.' 'How do you know all this?'

'Because while you and your men were gathering up Dionysius's body and bringing it here, I asked a few questions of the serving girl who brought him the drink tonight. She says that he brought the herbs to the kitchen after returning from the funeral. As usual, they were already mixed and crushed and gathered up in a scrap of cloth. Apparently Dionysius made quite a ritual of measuring and preparing them in advance. She herself added the watercress and grape leaves, then boiled and strained the concoction just before the meal.'

'She could have added the poison as well,' Crassus insisted. 'You must know something of poisons, Gordianus. What do you think it was?'

'I would guess aconitum.'

'Panther's-death?'

'Some people call it that. It's said to be palatable, so he might not have noticed it in his concoction. It's the fastest of poisons. The symptoms match – a burning in the tongue, choking, convulsions, vomiting, loosening of the bowels, death. But who,' I wondered aloud, 'would have known enough of such things to have obtained the poison and administered a proper dose?' I glanced at Eco, who pursed his lips. He had napped while I browsed through the various herbs and extracts in the house of Iaia at Cumae, but I had told him about them later.

Crassus stretched his shoulders and grimaced. 'I hate funerals. Even worse than funerals are funeral games. At least this will all be over tomorrow.'

'If only Dionysius had been able to tell us what he knew about the murder of Lucius,' I said, 'if indeed he knew anything at all. I should like to have a look in his rooms.'

'Certainly.' Crassus shrugged. His mind had already wandered to other matters.

I found the boy Meto in the atrium and instructed him to show us to the philosopher's chambers. We passed the dining rooms.

The meal had abruptly ended with the death of Dionysius and the withdrawal of the host and hostess, but many of the guests still lingered among the tables and couches. I paused and searched the crowd.

'Who are you looking for?' asked Meto.

'Iaia and her assistant Olympias.'

'The painter lady left already,' he said. 'Right after the philosopher started having his fit.' 'Left the room?'

'Left the house, for her own house at Cumae. I know, because she sent me to the stables to see that their horses were ready.'

'Too bad,' I said. 'I should very much like to talk with her.'

Meto led us farther up the hall and around a corner. 'Here it is,' he said, indicating the door to Dionysius's rooms.

The apartment consisted of two small rooms separated by a hanging curtain. In the outer room a round table was surrounded by chairs, set beside a window that faced the low wooded hills on the west. A clay urn was set atop a small table in one corner. When I lifted the lid I smelled the mingled scents of rue, silphium, and garlic. 'Dionysius's concoction. Poisoned or not, it should all be burned or emptied into the bay to be sure it harms no one else.'

The inner room, furnished with a Stoic's austerity, contained only a sleeping couch, a hanging lamp, and a large trunk.

'Not much to see,' I remarked to Eco, 'unless something has been hidden out of sight.' I started to open the trunk and found that it was clasped shut with a lock that required a key. 'We could break it open, I suppose. I doubt that Crassus would object, and we can ask the shade of Dionysius to forgive us. Indeed, it looks to me as if someone has already tried to force it open, and failed. See the scratches, and this scarred strip of metal, Eco? We shall need a strong, slender bar of steel to pry it open.'

'Why not use the key?' suggested Meto.

'Because we don't have it,' I said.

Meto smiled mischievously, then flattened himself on the floor, wriggled under the couch and emerged clutching a simple brass key in his tiny fist.

I threw up my hands. 'Meto, you are invaluable! Every household needs a slave like you.' He grinned and hovered over me as I stopped to fit the key into the lock. 'Indeed, Meto, I think you will grow up to be like those slaves in Plautus's plays, the ones who always know what's going on when their masters are too stupid or love-struck to see the truth.' Whoever had tried to force the lid had jammed the lock as well, so that I had to jiggle the key. 'Plautus's clever slaves always come in for a chiding from their jealous masters, but the world could never manage without them. Ah – there, it's open! What treasures did the philosopher find so valuable that he locked them safely away, I wonder?'

I pushed the lid up. Eco sucked in a breath. Meto started back.

'Blood!' he whispered.

'Yes,' I agreed, 'most assuredly, blood.' Atop the other scrolls that had been unrolled and laid flat within the trunk was a strip of parchment covered with tiny, crabbed writing, over which had been cast a great, spattered stain of blood.

'The missing documents?' I asked.

Back in the library, Crassus pored over the flattened sheets one by one. Finally he nodded. 'Yes, there are the records I was searching for, together with others I had no idea existed, full of all sorts of irregularities and cryptic references – expenditures and amounts received, itemized in some sort of secret code. I shall have to take them back to Rome with me after the funeral games. There's no way to make sense of it all without considerable time and study; perhaps my chief accountant can decode them.'

'I saw that the notation "A Friend" recurs several times, always connected to a sum of money, often a rather large sum. You don't suppose that could be a record of investments and disbursements relating to Lucius's silent partner?'

Crassus gave me a disgrunded look. 'What I really want to know is what these documents were doing in Dionysius's room.'

'I have a theory,' I said.

'I'm sure you do.'

'We know that Dionysius wanted to solve Lucius's murder, if only to impress you with his cleverness. Suppose he was ahead of us when it came to noticing the bloodstains on the statue that was used to kill Lucius, and had already concluded, even before I arrived, that Lucius was murdered in this room. Suppose also that he had some inkling of Lucius's shady dealings; after all, he lived in the house and might very well have noticed the flow of silver and arms, no matter how secretive Lucius might have been.' Crassus nodded. 'Go on.'