The officer nodded. ‘As far as we can tell. There’s a missing knife from the block on the counter.’

So we could assume that this wasn’t a premeditated murder; it had been the result of circumstance – unless the killer knew Diall’s kitchen well and had planned to use one of Diall’s own knives against him.

‘Was he married?’ My voice was weak and thready, barely audible to anyone but Winter. I cleared my throat and tried again. ‘Adeptus Diall,’ I said. ‘Was he married? Did he have a partner?’ Most murders were committed by someone the victim was already close to. Considering the circumstances, it was unlikely that a jealous spouse had done this to him but it was worth asking.

The police officer shook his head. ‘Divorced. We checked on his ex-wife. She’s been living in Spain for the past three years. We’re sending the local police round to her villa but we think we can rule her out.’ He glanced at me. ‘She’s not one of yours.’ Probably not a witch then. That was unusual but not necessarily suspect.

‘Have we uncovered anything?’ Winter asked, addressing the other witches.

The nearest one shook his head. ‘Unsurprisingly Adeptus Exemptus Diall had strong wards in place. No spell we can use will work here.’

Typical. Bloody Order witches and their desire for security. It seemed to bite them all back in the end.

‘There are no fingerprints except for those of Mr Diall and his housekeeper,’ the policeman said.

‘Adeptus Exemptus Diall,’ Winter growled.

I rolled my eyes. Even now, he remained a stickler for Order protocol. While the policeman bristled, I jumped in to fill the gap. ‘Has anyone found any, um, papers?’

One of the witches said, ‘There’s the Daily Express.’

‘Uh, no, I mean magical papers.’ I ignored Winter’s frown. If Diall had taken the missing Cypher Manuscripts either they were here or his murderer had left with them.

The witch pursed her lips. ‘Nothing beyond what you’d expect. A few interesting treatise on the workings of Myomancy but nothing unusual.’ Her eyes grew sharp. ‘Why?’

Winter coughed. ‘On the way here Ms Wilde was wondering whether a layman might have broken in to steal some magical artefacts or books.’

‘We can’t say for sure whether anything is missing but nobody appears to have rifled through his possessions. There are no obvious gaps on his shelves.’ She paused. ‘We did find this, however.’ She held out a piece of paper in her gloved hands.

I glanced down, confused. It just looked like random numbers to me.

‘It’s the…’

‘Coordinates for the library,’ Winter finished. He pointed towards the last few numbers. ‘And here, minus three at the end.’ He pressed his lips together.

‘That could mean three levels down,’ the witch interjected helpfully. She flipped the paper over and I realised it was a picture of the sceptre. I drew in a sharp breath. As usual, Winter didn’t react but he had to be thinking the same as me.