An Officer and a Spy

I have previously read Munich by Robert Harris and thought it very well done. He has written several books that range from alternative history to historical fiction to thrillers. This one focuses on the "Dreyfus Affair" that occurred in France in the 1890's...the "Belle Epoque" between the end of the Franco-Prussian war (when France lost Alsace & Lorraine) and the run-up to WWI.  Dreyfus, a Jewish officer in the French military was wrongly accused of being a spy, was summarily tried, publicly disgraced, and sent to Devil's Island as a solitary prisoner for several years.
The narrator of this work is George Picquart who was put in charge of the secret intelligence unit of the military shortly after Dreyfus' conviction. As he was familiarizing himself with the workings of a department and a job he never wanted to be a part of, he began to realize that the "evidence" against Dreyfus had been manufactured and that senior officers in the military were behind the conspiracy and subsequent coverup. At the same time, it became increasingly clear to Picquart that there was still someone spying for the Germans within the military. He risked his career and was even imprisoned for trying to exonerate Dreyfus and bring the real spy to justice. All the characters are historically accurate as is the timetable (over several years) of the affair.
The book is well-researched and, although a little slow at the beginning, will eventually engender the same outrage over the military's illegal and immoral behavior that the protagonist feels. The trial of Dreyfus inflamed an already pervasive anti-Semitic sentiment in the country. An insightful review from The New York Times provides the larger socio-political context that allowed this travesty of justice to occur. A glowing and detailed review from NPR, another from The Guardian. The Washington Post calls the book "mesmerizing."