Since 1903, when Erskine Childers warned of the rising tide of German militarism that preceded the first world war in The Riddle of the Sands, spy fiction has enthralled and chilled its readers by holding a cloudy mirror to the murkier corners of international politics. During the Cold War, John le Carré’s novels were hugely influential in shaping popular perceptions about the private manoeuvres behind the public antics.