Ross added an association line connecting Staunce to Vincent. ‘But then suddenly Vincent does need Staunce’s information again, because he needs our addresses. He can’t just look into Staunce’s head and find them, because Staunce doesn’t actually know them offhand; he needs to be told what to go and find out. So Vincent pays Staunce one more time –’ she looked again at her list of dates – ‘at 2 p.m. on the day he died.’

‘Why does Vincent get interested in us then?’ asked Costain. ‘What did we do that day?’

‘We interviewed Tunstall that morning,’ said Sefton.

‘So somehow Vincent knew about that,’ said Costain. ‘No, never mind somehow, there’s only one way this guy learns secret stuff: he must have used the scrying glass on Tunstall when he went to sleep after we saw him, and he’d have seen Tunstall’s memories of Jimmy telling Tunstall we believed him, and that we had abilities other units didn’t. Bloody hell.’

‘Staunce always took an afternoon nap,’ said Sefton. ‘First Vincent pays him, then he checks up on his motives, discovers something amiss, has him killed that same night.’

‘When do we start feeling shit going on in our dreams?’ said Ross.

‘From that night,’ said Sefton. ‘I think.’ They compared notes. None of them could pin it down exactly, but the date seemed right. They swore and got up and had to talk each other down from the fear, until Ross started shouting at them to let her finish. Quickly, they sat down.

‘Why was Vincent listening in on Tunstall’s thoughts?’ she asked.

‘Tunstall, like Staunce, was receiving under-the-counter payments,’ said Sefton. ‘If those were also from Vincent, maybe he wanted to make sure Tunstall wasn’t going to tell anyone about them.’

‘And he wasn’t,’ said Costain, triumphantly. ‘At least, not at first.’

He was pleased at the puzzled look that got from Ross. ‘How do you know that?’

‘Because it took Vincent so long to kill him. If you’re a gang boss, sometimes you suspect someone in your organization has grassed you up, and so you kill them, torture them, whatever. But if you had the power to know absolutely who was loyal and who wasn’t, to know who was even thinking about betraying you—’

‘You’d drop a lot fewer bodies,’ said Ross.

‘We were about to interview Tunstall again,’ said Sefton, ‘about the brothel business card. Vincent must have seen that Tunstall was wavering, that he might crack during that interview, and finally decided he wasn’t worth the risk.’

‘It’s kind of humane,’ said Costain, ‘compared to what we’re used to.’

‘And he waited to kill Jimmy,’ continued Sefton, ‘until Jimmy encountered him in his dreams and made some potentially incriminating notes about long barrows. Whatever they mean, those are the most important things. If Vincent knew now that we’d seen them, maybe he’d kill us too.’