Completing our party was a brother of Helena’s, Justinus. I worked with him in Rome and had also taken him on missions in rough country. I knew he would be reliable. Helena had begged me not to expose him to danger, but he was no longer a lad; it was his choice. He was keen to escape the bad atmosphere at home, caused by his brother’s new wife and pushy father-in-law. On this trip Justinus had brought his barmy batman, Lentullus. The dopiest, clumsiest ex-legionary in the Empire, Lentullus was devoted to Quintus in a wide-eyed way. He limped badly on one leg and would probably try to tame the Pontine flies as pets.

I planned that if we ran into hostility from local dignitaries, resentful of imperial interference, then Camillus Justinus, as a senator’s son with the smart travel clothes and uppercrust accent, could be shoved forward to charm them.

We first tackled officialdom at Lanuvium. I was right; we were given the brush-off. If there’s one thing I hate about travel outside Rome it is small-town magistrates who think they count for something. The petty toffs who ran Lanuvium had so little sense of proportion they called their town council the Senate and their magistrate a Dictator. That was the title used in ancient times for a leader with unrestricted powers who was called upon to rescue the nation in an emergency. On mention of the Claudii, the Lanuvium Dictator rapidly assumed other emergency powers: declaring that this problem was outside his jurisdiction. He kindly suggested we try Antium instead.

He had cow dung on his boots and I wasn’t certain he could read—yet he managed to dismiss Laeta’s request for civic aid as briskly as if he was swatting wasps on a saucer of relish.

‘I’m getting a feel for this,’ Petronius remarked in annoyance as we left.

‘You mean,’ suggested Justinus, ‘it feels like stepping in a slurry pit?’

‘And helplessly falling over!’

We spent the next half-hour despondently embroidering this with such details as falling in the manure while wearing your best cloak and with a girl you fancied watching . . .

Our detour to Lanuvium was partly a waste of time, but we did see Silanus. Petronius had asked him a few questions that confirmed the body found in the tomb was his uncle: a man in his sixties, nearly bald, thin build; usually wearing a lapis signet ring, which had not been found. I saw Petro thinking that the killer might have kept it as a trophy and that if we ever caught up with him, the ring might be good evidence. Her nephew said Livia Primilla was about fifteen years younger; in good health, blue eyes, greying hair, kept herself nicely, wore good clothes and jewellery. Unfortunately, even though they dealt in statues and must know the artistic community, the couple had never commissioned portraits of themselves.