‘Looks as if our theory’s right,’ Blackthorn says. ‘Maid and mistress changing bodies when they went into Dreamer’s Pool.’

‘Why would she tell that story right now? Isn’t that a bit odd?’

‘I asked her to tell it. When she said she knew the last wise woman, the one before me. I knew there was an old tale about the pool, something about pigs, but nobody else remembered it. Grim, this isn’t much help. Maybe it shows that Ciar and Flidais switched over. But one of them drowned. Taking Flidais for a nice little swim in Dreamer’s Pool can’t bring the dead girl back. As for odd, this is no odder than Conmael telling you I’d be at Silverlake. How could he know what I’d do?’

‘Knows you better than you think. That’d be my guess. Knew you’d want to see Ness again before you left. And Emer.’

Too dark to see Blackthorn’s face, but I bet she’s grimacing at that. ‘I’m not the good person you think I am, Grim. I’m a messy tangle of doubt and hate and anger and bitterness. If Conmael thinks he can make me into something different, he doesn’t know me at all.’

I don’t say anything. She’s got it wrong. But no point telling her that. She won’t believe me.

‘Grim?’

‘Mm?’

‘We need a plan. It’s not long until full moon and the prince’s council. And after that they’ll be riding off to their wedding and it will be too late. But pushing Flidais into Dreamer’s Pool isn’t going to achieve anything, even supposing we could convince her to go back over there. What do we do? Tell the prince the story we heard tonight and say we can’t do anything more? Tell him Flidais and Mhairi lied to me? Confront Flidais with what we suspect? None of those will do any good. Maybe we should suggest he marries her anyway, since the woman of his dreams is dead.’

I’m thinking hard. ‘You could ask Conmael,’ I say. ‘Since he seems to know all sorts of things he shouldn’t know. He might have the answer, if there is one.’

‘A pox on Conmael,’ says Blackthorn, so quiet the rain nearly swallows it. ‘We’re solving this ourselves. We need to talk to someone who was there that day, when Ciar was drowned.’

‘You were there.’

‘Not at first. By the time I reached the pool she was lying dead on the shore. I want to know exactly how it happened. We’re missing something, and it’s not pigs and cheese.’

‘Couldn’t you ask Flidais’s ladies? Not Mhairi, the other ones?’