The Space Trilogy (also known as The Cosmic Trilogy or The Ransom Trilogy) is a series of science fiction novels by C. S. Lewis. The trilogy consists of Out of the Silent Planet (1938), Perelandra (1943), and That Hideous Strength (1945). A philologist named Elwin Ransom is the protagonist of the first two novels and an important character in the third. Source: Wikipedia (en)