3/4. Ever since the Turkish army invaded and occupied northern Cyprus in 1974, the partition of the island between ethnic Greeks and Turks has seemed set in stone. But the first green line through the capital was drawn ten years earlier by a British general. Throughout 1964 British troops were on the island, supposedly for peacekeeping. But were they really bringing peace? Mike Thomson uncovers the existence of a British spy-ring and examines evidence that suggests that the real motives of some of the peacekeepers were less than honourable. Producer Jolyon Jenkins