Meet Tristan Hart, a brilliant young man of means. The year is 1751, and at the age of twenty he leaves home to study medicine at the great hospital of St. Thomas in London. It will be a momentous year for the intellectually ambitious Mr. Hart, who, in addition to being a student of Locke and Descartes and a promising young physician, is also, alas, psychotic. He is obsessed with the nature of pain and medically preventing it, but--equally strong and much harder to control--is his obsession with...