Signals intelligence (SIGINT) played a pivotal role in WWII but while the technological achievements are well documented the agents whose missions - and lives - depended on it get overlooked.

Britain’s Special Operations Executive was one of the War’s best-known clandestine forces and France its largest operation.

Historian Dr Kate Vigurs in her new book - Mission France: The True Story of the Women of SOE - collects the interconnected stories of 39 of these secret agents for the first time: women selected from all walks of life who risked betrayal and death for freedom.