The seventh instalment of Dan Mackmain’s adventures makes this the longest continuous sequence of novels that I’ve written. Okay, I actually reached that point with the last book, The Green Man’s Quarry but I’ve only just thought about this. The Tales of Einarinn came to a natural pause after five volumes. The subsequent books in the World of Einarinn timeline were a series of four novels, followed by two trilogies. With each of those sequences, I was determined not to rewrite a story I’d already told. Shifting focus to a different part of that fantasy world with a new cast of characters was a key part of ensuring that.

So how can I keep writing the Green Man books without repeating myself? It turns out elements embedded in these stories from the start are very helpful. I decided Dan’s life would be grounded in everyday reality. Writing epic fantasy novels showed me how a solid foundation makes the magical far more believable. With these books, that means a year or so between each story sees a year or so pass in Dan’s life. His relationships develop and his priorities change. That makes new demands on him and I can find new ways to threaten him.

These books are rooted in British folklore. This is a vast and varied resource. The more I read, the more I find to spur my imagination. I don’t necessarily find complete stories. Most local legends are single incidents, often tied a particular landscape feature or an old building. A lot of these stories are very similar, even when they’re set hundreds of miles apart. None of this is a problem. As I read these variations, I can use common threads to weave stories into the underlying mythology that’s evolving through this series. Where I find contradictions and exceptions, those can remind the reader not to take anything for granted. Where mentions of a monster are little more than fragments, I can devise something that’s both familiar and wholly new.

Then there’s the catalyst. The creative process that has emerged for these books is very different to my approach to writing an epic fantasy novel or a historical murder mystery. I plan those in detail from the start, and I tailor my research to the needs of the plot I’ve already worked out. Each Green Man book starts with me gathering assorted, apparently unrelated ideas from my folklore reading, from places I visit, from conversations with like-minded friends. I make note of news stories about rural life and concerns which will affect Dan and his friends. At that stage, I genuinely have no idea what the next book will be about.

Then I will come across something that suggests a way to tie these ideas together. Once I have that catalyst, the story starts to take shape. Its internal momentum shows me where and when to draw the next element in. Now my research is about finding the people and resources to tell me things I had no idea I would need to know. I will be well into writing the novel before I see the ending come into focus ahead. I would never have imagined I would be working this way, but the experience is as exciting as it has been unexpected.

So what was the catalyst for The Green Man’s War? When we were visiting Burford one day last winter, my husband saw a small bronze statue of three dancing hares in a jeweller’s shop window. Regular readers will understand why that caught his eye. We went in to buy it, only to discover the shop door should have been locked and the ‘Closed’ sign put up. A distracted member of staff had followed the usual routine on auto-pilot. The manager and staff were actually in the shop that morning to compile an insurance claim after being robbed the week before. A gang of men armed with hammers and knives had ambushed the keyholder outside, forced their way in, and stripped the shelves and display cases bare. The nice people in the shop were happy to sell us the little statue, once they had told us all about it.

That got me thinking. What would Dan do, faced with that situation? Why might something like that happen to him? I’d read a few myths that mentioned jewellery. Ideas started coming together…