Challenging the prevailing belief that Mark Twain s position on religion hovered somewhere between skepticism and outright heresy, Lawrence Berkove and Joseph Csicsila marshal biographical details of Twain s life alongside close readings of his work to explore the religious faith of America s most beloved writer and humorist. They conclude not only that religion was an important factor in Twain s life but also that the popular conception of Twain as agnostic, atheist, or apostate is simply wrong. Heretical Fictions is the first full-length study to assess the importance of Twain s heretical Calvinism as the foundation of his major works, bringing to light important thematic ties that connect the author s early work to his high period and from there to his late work. Berkove and Csicsila set forth the main elements of Twain s countertheological interpretation of Calvinism and analyze in detail the way it shapes five of his major books Roughing It, The Adventures of Tom Sawyer, Adventures of Huckleberry Finn, A Connecticut Yankee in King Arthur’s Court, and No. 44, The Mysterious Stranger as well as some of his major short stories. The result is a ground-breaking and unconventional portrait of a seminal figure in American letters.