R. L. Graham is a husband-and-wife team of historians and writers with a broad range of interests in many periods of history, including the belle époque and the tumultuous years leading up to the First World War and the post-war re-ordering of the world. They are very much drawn to the shadowy world of crime, espionage and political intrigue. They are particularly fascinated by historical mysteries: things which have happened but have no apparent explanation. Originally from Canada, they now live in a small village in Devon. Marilyn Livingstone, one half of R. L. Graham, was diagnosed with pancreatic cancer while this book was being written. She passed away in September 2023.