Peter Cotton, a young Intelligence officer is sent to Spain in September 1944. The war in Europe is drawing to a close; formerly neutral Franco is edging closer to the Allies. Cotton has been sent to investigate the activities - and then, just as he arrives, reports of the death - of a British agent, May, who has spent much of the war in the remote outpost of Cadiz monitoring the Spanish smuggling of raw materials to aid the Axis war efforts, in strict violation of the terms of neutrality. Cotton is briefed in Madrid by Houghton, an agent working at the British Embassy. He also meets Houghton's partner, Marie, half-Jewish, who has helped many Jews escape through Gibraltar. They brief him on Franco, his paranoid fears of assassination, his capricious cruelty and his duplicity. Even as he gets on the train to begin the long, hot journey to Cadiz, it is clear that Cotton is being watched. And when he arrives in the rundown port, almost on the brink of starvation, it is clear that his visit has been expected. Reluctantly allied with the sinister Ramirez, the local police inspector, Cotton has to investigate May's death and what exactly led him to sever all contacts with his London controllers in the months leading up to his disappearance. But Cotton is not the only person with an interest in finding out what May had been doing. Cadiz is a hotbed of rumours and shifting political alliances in this, the final phase of the war and Cotton must navigate his way not only through local tensions but also through the uncertain loyalties of a bizarre expatriate community, including an unhelpful consul, a German woman married to a wealthy Spaniard and mysteriously marooned in the town, an apparently innocent Irish girl, and a strange British couple who chose to remain in Spain while the rest of Europe was engulfed in flames... What Cotton discovers amid the stifling heat and dust could just tilt the emerging balance of post-war power.