Since the inception of the Secret Service Bureau back in 1909, women have worked at the very heart of British secret intelligence - yet their contributions have been all but written out of history. Now, drawing on private and previously-classified documents, leading historian Claire Hubbard-Hall brings their gripping true stories to life. From encoding orders and decrypting enemy messages to penning propaganda and infiltrating organisations, the women of British intelligence played a pivotal role in both the First and Second World Wars.