When the history of British codebreaking is told, the story is often a men-only preserve (for example, of the top fourteen listed actors in Bletchley Park-set The Imitation Game, only one is a woman). That perception completely ignores the fact that the vast majority of codebreakers were in fact women. And foremost among them was one who is largely unknown to the public, and whose activities were a secret even to her closest contacts - Emily Anderson.

Anderson was a leading member of British intelligence for over three decades. She played key roles in both World Wars, worked in Bletchley Park and in the Middle East, and was reckoned among the top three female codebreakers in the world. Her work coincided with her other great love - music. She is famous in musicology circles as being the first to effectively decipher the letters and diaries of Mozart and Beethoven. In 1961 Germany awarded her their highest honour, the Order of Merit First Class, completely ignorant of the fact that the interpretative skills they were honouring were the same utilised to defeat their military only a few years previously.

Secrecy was the keyword of her life, as she also had numerous relationships with other women at a time when such was not generally accepted. That few are familiar with her name is no surprise. Even those close to her had little idea that she had such a significant role in international affairs. Now, this startling new narrative of her life, complete with new material and sources The Queen of Codes will place Emily Anderson at the forefront of great British codebreakers.