Literary scholar, novelist, and Christian apologist, C.S. Lewis was a remarkable and enigmatic man. He is perhaps best known today for his popular series of children's books, the Chronicles of Narnia, which continue to sell more than a million copies a year. He also wrote science fiction in the form of interplanetary fantasies - a series of three novels known as the Ransom Trilogy. This book offers the first full-length critical assessment of that trilogy, placing the three volumes in the context of Lewis's life and work. David C. Downing reveals the autobiographical and theological subtexts of Out of the Silent Planet, Perelandra, and That Hideous Strength, showing as well how much Lewis the classical and medieval scholar influenced the work of Lewis the creator of interplanetary fantasies. Downing also examines the chief imaginative and intellectual sources of the trilogy and addresses persistent issues raised by reviewers and critics: Was Lewis's lifelong devotion to fantasy a mark of intellectual independence or a case of "arrested emotional development"? Were his views on women sexist, even misogynist? How much of his critique of modern science and technology was well informed and how much the result of prejudice or habitual suspicion of all things modern? A brief appendix on "The Dark Tower" fragment provides what background is known about this mysterious document, summarizes the story as far as Lewis developed it, and comments on how this unfinished work fits in with the Ransom books published during Lewis's lifetime.