Middle books are sometimes tricky but I had a whale of a time with this one. It veered from my imagined synopsis almost right away and set off on its own course without so much as a 'by-your-leave'. So I just shut my eyes and let myself be swept along.

In Stone & Sea, I was able to develop Jonah's new-found powers (the ability to change history - or rather the memory of history, which is somewhat different). The strange qualities of the watery location also demanded that I soak the characters in charm for a while. Some of the things that happened as a result surprised me. And the 'Annie's Journal' chapters proved a great to way to introduce a new voice and viewpoint, which helped keep the writing fresh.

I had fun with some of the standard fantasy stereotypes. Mermaids were too obvious for a sea-going tale, so I went for selkies and a giant sea goddess who's half-woman, half-whale. Don't ask where she came from - I've no idea.

In Stone & Sky, I'd introduced a new dragon character called Kythe. Stone's peculiar brand of time travel gave Kythe the chance to explore the early history of her race, a time period I'd left deliberately vague in Dragoncharm and its sequels. While writing Stone & Sea, I came to realise this time travel business was the key to wrapping up the whole trilogy.

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