This volume is aimed at anyone with an interest in the secret underworld of political and military intrigue. What is it like to be a spy? What makes someone decide to lead a secret life? What qualities do such people have in common? How do they get away without being detected? How do they slip up? How are they found out? What makes their life so extraordinary? What makes their life so ordinary? Why did Kim Philby become a spy? What events first sparked Sir Colin McVean Gubbins's interest in irregular warfare? What part did businessman Greville Wynne play in the Cuban missile crisis? And who, exactly, was Guy Fawkes? This text answers these, and other, questions.