Eye Of The Needle: by Ken Follett.

Future of civilisation and humanity depended on Allies winning, and before Normandy invasion it looked even chance - albeit not as bleak with need of fortitude as when Britain was going it alone in face of impossible odds - so all the more it was vital the invasion succeed. Allies had brought about an elaborate deception with Patton in East Anglia to give the impression that the invasion would be spearheaded from there at Calais, with shortest distance from England to France to Germany involved, and Patton being the star of various battles until then.

What if the deception was discovered, what if there was a spy, a needle in a haystack, a German who looked and spoke as an upper class Englishman and no one had a clue to his truth, and what if such a needle could get to a submarine in sea off English coast with a launch and alert them that East Anglia was a ruse after all?

If indeed it all happened, we are lucky the lonely woman who was falling for the stranger she and her husband saved after his launch crashed in a strong gale off their island was not blinded by love or even blinkered - for when she discovered her handicapped husband's death, and realised moreover that he had not fallen off a cliff after all but was murdered by the stranger, she did not hesitate in using all her mind and other faculties in trying to overcome whatever the stranger's aim in all this.

She did not know even then - although her husband had been suspicious to begin with and found out, which is why he was murdered - that it was not about jealousy but about the war and espionage. When she did discover that, she managed to stop him from giving it away. How, makes a very worth acquainting oneself with sort of a thriller. And if any of it is true history in fact, she deserves a supreme award of recognition and honour.