I started with Freyja. No reason, except that she was the weakest link in the chain. Odin had a soft spot for her, and if my plan worked, I meant to cut him as deeply. Now the Goddess of Desire was vain and, since my encounter with the Tunnel Folk, had never ceased to question me about their treasures, especially the jewellery I’d seen on my visit to World Below.

‘Tell me more,’ she would say, lounging on her silken couch, eating fruit, attended by her maidens. One of them was Sigyn, whose interest in me seemed to increase the less attention I paid to her. Next to Freyja she looked plain, which I guess was Freyja’s intention. Freyja herself was peerless, of course; creamy skin, red-gold hair, a rack like you wouldn’t believe. Her amber-eyed cats purred at her feet, the air all around her was scented. No one – not even I – was wholly impervious to her charms, but I preferred the wilder type, and besides, I had more important things on my mind than romance.

‘Well,’ I began, helping myself to a grape. ‘The sons of Ivaldi may not have been judged the best craftsmen in the Nine Worlds – although I still dispute this – but they are undoubtedly the finest goldsmiths I’ve ever seen, as I’m sure you’d agree, if you’d seen their work. I’m talking about gold, Freyja. Necklaces, bracelets, the lot – shining like scraps of sunlight. And there was one particular piece – a necklace like you’ve never seen. A choker, broad as the length of your thumb, made up of links so delicately crafted that it might almost be a living thing; moulded to every curve of your neck; gleaming, reflecting, perfecting—’

Freyja gave me a sharp look. ‘Perfecting?’

‘Sorry. My mistake. Of course. My lady, you’re perfect already.’

I grinned inside. The lure was thrown. After that, it was only a matter of time before Freyja went in search of it. I watched her from afar. Not for long. Sure enough, as I’d anticipated, I saw her leave Asgard one morning – on foot, without her chariot, without even a single handmaiden to assist her – and cross the plain of Ida in search of the Sons of Ivaldi.

I followed her in bird form, soaring high above her head, and when she entered World Below through the Forest of Ironwood, I changed myself into a flea and dropped into her cleavage, to find out just what kind of deal she was ready to make with the Maggots.