Joan Arkle, a tireless climate change activist, is passionate about her beliefs. She has taken her campervan to the Lake District, to be able to live among the hills she loves. Here there is ample scope for her trade as a wildlife photographer. Here, too, there is opportunity to make a difference by campaigning against global warming.

But her time in Cumbria proves challenging. Somehow her activities attract hostility. Increasingly she makes enemies.

And then, one evening on a quiet by-road, her campervan is firebombed.

Who is responsible? And who precisely is Joan Arkle? These are the questions which both DI Chrissy Chambers of the Cumbrian Police and Nick Potterton, once a successful London journalist but now a struggling local freelance, find themselves trying to answer.

Andrew Bibby's latest crime mystery is set among the beauty of the mountains and lakes of England's most popular National Park.