Think of spies and you might picture a suave James Bond-like gentleman working for a rich and mysterious organisation with all the characteristics of a traditional British public school. In fact, it is only very recently that official intelligence organisations were founded and spying was established as a profession. Britain’s permanent secret service was founded in the twentieth century. It was then that spying started to lose its stigma as a dishonest and disreputable way of making a living and started to become seen as a legitimate way of collecting military intelligence.

However, even before spying became a professional business, spies played an important part in British history. There is no better place to find out about these shadowy figures than in the files of the National Archives.

Here are the stories of three spies and the nature of espionage in their time. There is the Elizabethan spy, whose loyalties and responsibilities were sometimes ambiguous; there is the nineteenth century spy, who would have denied being a spy at all; and the Second World War spy, who operated in a complex network of agencies and alliances.