We asked about his brother Probus. Virtus said men had come and arrested him—Silvius and the Urban Cohorts, presumably. ‘Why didn’t they get you at the same time?’

‘I heard them coming.’

We took him with us to Antium, where we joined up with Silvius. Silvius confirmed he had Probus in custody. Probus seemed to be breaking ranks and denouncing Nobilis, though it was too early to say if he would distance himself enough to give us evidence. When Silvius wanted to question Virtus, I had had enough with the other twin, so I gave him the prisoner without quibbling. Justinus and I sat in. I insisted on that.

In two days of hard questioning, Virtus said little useful. His line now was that he had never had anything to do with any of his brothers’ cruel practices—and, as he knew well, we had nothing to tie him to the murders.

‘None of us ever knew what Nobilis was up to.’ That tired cliché. ‘These things you are saying about him and Pius are terrible. Thank the gods our father will never know about it.’

‘Aristocles was no moralist! Look at the disgusting rabble he and Casta produced. Strong family bonds, have you?’ asked Silvius, insinuating.

‘Oh I see your game! I repudiate my brother. I reject Nobilis. If he and Pius did those things, I dissociate them from our family. They shame us. They are blackening the family name.’

‘What family name? Don’t make me spew.’

Virtus just stared at Silvius. He was not a clod. None of them were. That was how those of them who committed the crimes had covered up their tracks for so many decades.

‘We’ll get the truth,’ sneered Silvius. ‘Probus is here in custody, you know that. Your Probus seems a fellow with a conscience. Probus has begun telling us a lot of helpful things—all about his perverted brothers.’

‘Probus is just as bad as them,’ scoffed Virtus.

When Silvius needed a break, I was given a go. ‘Tell me about your connection with Anacrites, Virtus.’

‘Nothing to say.’

‘When did you find out about him?’

‘Around two years back. We went up to Rome and asked him for work. He thought he could use us, so it was fixed up. I know when it was, because our mother had just died.’

‘Casta? Was her death something to do with you going to see Anacrites?’

‘Yes and no. When we lost her, we felt cast adrift.’

‘Oh you poor little orphans!’

‘Have a heart, Falco!’ Justinus broke in, grinning. Silvius let out a short laugh too. He had bad teeth, not many left.

I had remembered something someone told us about Casta. Unexpectedly, I strode up, grabbed the prisoner by his hair, then turned his head to demonstrate he had part of an ear missing. ‘Did your mother do that to you?’ I yelled.

‘I deserved it,’ said Virtus, immediately and without blinking.