The Human Factor highlights a man, Maurice Castle, who is driven at times to make choices based on love and an often-misplaced sense of moral duty that have some pretty serious consequences for himself and others.
Castle is an agent in MI6, and as the book opens, a leak has been discovered in his division. Suspicion falls on his partner, Davis, who seems to have a lot more money than an agent in his position should -- he bets,he drives a Jag -- and he's also a pretty heavy drinker. Castle is older, near retirement, and leads a pretty quiet life, seemingly beyond reproach. But mild-mannered Castle is the one with the secret life, starting during his time in South Africa. Choices that Castle made then catch up to him in his present, leading up to a chain of events which unravel his quiet and ordered life in England with his family.
This book really is not really a story about espionage or the cold-war intelligence game. Castle marches to his own inner sense of personal morality, as noted by his mother at one point, where she says:
"You always had an exaggerated sense of gratitude for the least kindness. It was a sort of insecurity ....You once gave away a good fountain pen to someone at school who had offered you a bun with a piece of chocolate inside."
It hit me while reading that this "sense of gratitude" is the key to understanding Maurice Castle -- and it offers an insight into the reasons behind Castle's actions. For Castle, loyalty begets loyalty, but the reader may make judgments based on his or her own understanding of patriotism or morality that misconstrue Castle's actions completely. Understanding Castle as a human being rather than as a spy or as a British citizen is key to understanding this story.
The Human Factor is truly an awesome novel. It starts out very slow, but the tension builds as the book progresses until you're so caught up in it that you can't look away. I'd definitely recommend it to people who enjoy British literature, and to those who enjoy reading about the grayness of human morality. It's also pretty decent as a novel of espionage if you don't want to get into the deeper aspects of the novel. Very highly recommended.