The C.S. Lewis Space Trilogy 3-Book Box Set collects all three of Lewis's celebrated science fiction novels in a single boxed set. The trilogy follows Dr. Elwin Ransom, a Cambridge philologist, on a series of extraordinary interplanetary journeys that blend scientific adventure with deep spiritual and philosophical themes.

The three novels included are Out of the Silent Planet (1938), in which Ransom is transported to Mars (Malacandra) and discovers a world of unfallen beings; Perelandra (1943), set on Venus, where Ransom must prevent a second Fall on a pristine new world; and That Hideous Strength (1945), which returns to Earth for a climactic struggle between cosmic forces of good and evil, drawing on Arthurian legend and modern institutional corruption.

Together the trilogy is regarded as a landmark of Christian science fiction and literary fantasy, praised for its imaginative world-building, richly drawn alien cultures, and exploration of themes including temptation, redemption, and the nature of good and evil. The series has earned an average rating of 4.19 out of 5 stars across more than 12,000 reader reviews.