I sighed gently. ‘No fooling you, grandma! I work for the government; I want information.’

‘What will you pay?’

‘The going rate.’

‘What’s that?’

I looked in my purse and showed her a few coins. She sniffed. I doubled it. She asked for treble; we settled on two and half.

She toddled into a corner to brew herself some nettle tea before we started. I gazed around, impressed that one elderly woman could have collected so many doilies and corn dollies, so many horrible old curtains, so many amulets with evil eyes or hieroglyphs or stars. The air was thick with dust, every surface was crammed with eccentric objects, the high window was veiled. I bet every superstitious old woman from a two-mile radius came here for her special Thursdays. I bet half of them left her something in their wills.

Nothing that smacked obviously of witchcraft was out on view. The desiccated claws and vials of toad’s blood must be behind the musty swathes of curtain.

Eventually she settled down with her tea bowl and I learned Claudius Virtus was a regular at the seances. ‘He was interested in the Dark Side. Always full of questions—I don’t know where he got his theories. From his own strange brain, if you ask me.’

‘Are you going to tell me what you do at your meetings?’

‘We try to contact the spirits of the dead. I have the gift to call them up from the Underworld.’

‘Really? And did Virtus ask about anyone in particular?’

‘Usually he watched the rest. He tried to talk to his mother once.’

‘Did she answer?’

‘No.’

‘Why would that be?’

Abruptly, Alis turned confiding: ‘I got the creeps, Falco. I don’t know why. I just felt I didn’t want to be in the middle of that conversation.’

‘You have some control then?’ I asked with a smile.

The seer sipped her nettle tea, with the manners of a lady.

She told me Virtus had never missed a meeting until a few weeks ago. His mother—Casta—had died a couple of years before, he told Alis; he claimed to be close to her and said all the family adored the woman.

‘My information is she was vicious,’ I said. ‘She had twenty children and was reputed to treat them all very coldly.’

‘That’s your answer,’ replied Alis comfortably. ‘It explains Virtus. He tells himself she was wonderful; he wants to believe it, doesn’t he? In his poor mind, his ma is a darling who loved him. He misses her now, because he wants her to have been someone he should miss. If you were to say to him what you just said to me about his mother, he’d deny it furiously—and probably attack you.’ I believed that.

Alis had winkled out of him that his father died before his mother, and that he had other relatives, some in Rome. ‘More than one?’