In Newgate Street, in the city of London, stand the meagre ruins of Christ Church. On the same site once stood a royal mausoleum set to rival Westminster Abbey in the 14th century. Among the many crowned heads buried there was Isabella of France, Edward II's queen - one of the most notorious femme fatales in history. But how did she acquire her evil reputation? And is it justified? Alison Weir's engrossing biography sets out to put the record straight.