The British involvement in Greece during the 1940s was neither a heroic act of defending the freedom of the Greeks nor a dark conspiracy for its suppression. The British intelligence services were guided by the Foreign Office in implementing a policy that throughout this period remained much more consistent than it seems at first glance: defending British geostrategic interests in the Eastern Mediterranean, it sought to maintain a political system eroded by the decades of the National Schism, both by supporting the king and his exiled government and by countering the communist left and its popular support in the country. Utilizing extensively British, American, and Greek archives, many of which have recently become available to researchers, the book examines the influence and evolving role of British intelligence services – and specifically the SOE – in Greece: the support they initially offered to the Resistance with operations aiding the British war effort; their subsequent intervention in the internal disputes of the guerrilla movement, alongside the exercise of a critical political and diplomatic role; finally, the collapse of their understanding with the EAM and their greater or lesser involvement in the events that led to the Civil War (a matter that still divides the scientific community and public opinion). As the study documents, the more the EAM became uncontrollable, the more desperate the British efforts to undermine it appeared. Whether in the early months of World War II or during the open conflict of the December events and their aftermath, the political directives and methods followed by the intelligence services remained the same; however, they were applied with increasing intensity and cynicism, despite any disagreements and regardless of their tragic consequences.