Book A War of Wyverns — S. F. Williamson

Vivien Featherswallow has translated a secret language of dragons – sparking an all-out civil war, with dragons and humans fighting on both sides, in the process.

And after defeating Prime Minister Wyvernmire and escaping Bletchley Park, Vivien has become the reluctant face of the rebellion – and been labelled the most wanted criminal in Britain. But what good is a rebel who must remain in hiding, powerless to help her friends?

Unsure of her purpose, and torn with doubt about the life she thought she was meant to lead, Vivien travels to the remote Scottish Isles to find a mysterious, long-forgotten species of dragon – one which might hold the key to ending the war… forever.