Marsh’s nose twitched. ‘I turned the water into vodka. I was trying to drink it when I fell in.’

I raised my eyebrows. No wonder there weren’t any ducks around. I didn’t think paddling around in a lake of alcohol would be the favourite pastime of a bird – although it didn’t sound all that bad to me. ‘You don’t like wine?’ I asked.

‘Huh?’

‘Never mind.’ I kept my eyes on him. ‘When else?’

He twitched again. ‘When else what?’

Either the man had the memory of a goldfish or he was good at avoiding answering questions. ‘When else did you visit Arcane Branch?’

‘There was the time I lost the building specs for Windsor Castle,’ he said. ‘I don’t know what all the fuss was about. They turned up.’

Intrigued, I drummed my fingers against the table top. ‘Where were they?’

He shrugged. ‘In a drawer. I’d forgotten I’d put them there.’

‘A drawer where?’ Winter asked.

‘At home.’

Winter sat up even straighter than normal. ‘You took important documents home with you and lost them?’

‘It was only the one time,’ Marsh grumbled. He rubbed at his face. ‘Is this going to take long? I really don’t feel very well at all. I think I might be sick.’

Winter picked up a small bin. ‘Here you go,’ he said without a trace of a smile. ‘Be sick into this.’

Marsh took the bin and hugged it to his chest. I really hoped he held onto the contents of his stomach; I rarely did well with other people’s vomit.

‘So,’ Winter said, all but rubbing his palms together. ‘You have experience of taking documents which don’t belong to you. Why don’t you tell us what you did with Volume 9?’

‘Volume 9?’ Marsh whispered. ‘You mean of the Cypher Manuscripts? You mentioned that before.’

‘Yes.’ Winter folded his arms. ‘I did. Where is it? We know you’ve burnt at least one page. Where is the rest?’

Marsh swallowed. ‘I don’t know anything about it. I’ve never been near the Cypher Manuscripts. I’ve never even looked at them in the library.’

Winter scratched a note to himself; it should be easy to check whether Marsh was telling the truth or not.

The witch continued. ‘I wouldn’t take them. I wouldn’t even know how to take them. Aren’t they warded?’

Winter’s lip curled. ‘Usually, yes.’ His jaw tightened. ‘But you found a way round that, didn’t you? You circumvented the systems, almost killing Ms Wilde and me in the process. What is it you’re really after, Marsh? Is it power? You might as well tell us. The Manuscript will do you no good in prison.’

‘I don’t know what you’re talking about! I’ve never touched it! I told you!’

‘Then why did we find clear evidence that you had in your home?’

‘I don’t know!’

Winter exhaled then abruptly changed tack, softening his voice. ‘What happened with Adeptus Diall? Did he threaten you? Is that why you killed him? We know it wasn’t premeditated, Oscar. Was it self-defence? We can help you if it was. We understand that Diall could be difficult.’