I like Alan Judd's 'spy' writing, including his 'Charles Thoroughgood' series and the biography of C, but this book included at its heart errors of basic physics that even a better-than-average A-level school Physics student could have spotted. As someone whose career has been focussed on the physical sciences this was not an issue I could ignore. What might have scored more stars otherwise gets down-rated accordingly since the errors might so easily have been filtered out.