Established by the Catholic Church in 1231, the Inquisition continued in one form or another for almost seven hundred years. Though associated with the persecution of heretics and Jews and with burning at the stake its targets were more numerous and its techniques more ambitious. The Inquisition pioneered surveillance, censorship, and scientific interrogation. As time went on, its methods and mindset spread far beyond the Church to become tools of secular persecution. Traveling from freshly opened Vatican archives to the detention camps of Guantanamo to the filing cabinets of the Third Reich, the acclaimed writer Cullen Murphy traces the Inquisition and its legacy, showing that not only did its offices survive into the twentieth century, but in the modern world its spirit is more influential than ever.