Dry-lipped, I said: ‘Brother, please. I promise I’ll never defy you again. I’ll show you how to fight Surt. I know how to do it. Odin. Please . . .’

‘It’s me,’ said a voice.

‘Sigyn?’

I managed to open my eyes. They still burned but now I could see a shadowy outline next to me. The shape seemed to be holding something between my face and the serpent. As my vision slowly cleared, I saw that it was the large glass mixing bowl that Sigyn used to made cake batter. The sides of the bowl were already streaming with the serpent’s venom.

‘It’s all I had to hand,’ she said, looking at me tenderly. ‘Silly old Snakey thinks he can get to you through the glass. He’s a nasty one, isn’t he? Nasty, mean old Snakey.’

Snakey hissed, as well he might.

Sigyn went on: ‘Poor angel. You must be so uncomfortable. Still, I’m here now. Try not to move. You’ll only hurt yourself, you know.’

My eyes were still streaming – with pain, I think, or perhaps they were tears of gratitude. For a moment the thought of release filled me with euphoria.

‘Oh, Sig,’ I said, ‘I’m so glad you’re here. I’ve been such a rotten husband. I promise you, that’s going to change. Just get me off this rock. Please.’

‘Oh, Loki,’ she said. ‘You’re so sweet. And I really believe you mean it, too. But I can’t let you go.’

‘Say what?’

‘Well, you’re here for a reason, dear. Criminals have to be punished. And if I let you go, I’d be letting down Odin and all the others.’

For once, I was wholly lost for words. ‘What?’ I repeated.

Sigyn smiled. Through a haze of tears I saw her face; tender, loving, immovable. ‘Well, you did kill Balder,’ she said. ‘That’s why Odin killed our boys. So in a way, you’re responsible.’

I started to panic.

‘No, I’m not! Sigyn, please! Let me go!’

‘Stop moving. You’ll knock the basin.’

I looked at her in disbelief. She looked serene – and quite unhinged. Had the deaths of Vali and Narvi finally brought her to the edge? Or was this the scenario she’d always secretly wanted – to have me to herself for good, helpless and in her power?

‘I brought some fruitcake for later,’ she said. ‘If you like, I’ll cut you a slice.’

‘Cake,’ I said. ‘You brought cake?’

‘Well, cake always makes me feel better,’ she said. ‘It’s cherry and almond. Your favourite.’

‘Please! You have to let me go!’

‘I don’t, and I won’t.’ Her mouth tightened. ‘Now don’t make me cross, or I might have to go for a little walk to calm my nerves. And if I do that, there’ll be nobody to hold this between you and Snakey.’