What was the name of C.S. Lewis’s science-fiction trilogy?

C.S. Lewis’s science-fiction trilogy is called The Space Trilogy.

The series consists of Out of the Silent Planet, Perelandra, and That Hideous Strength. The books follow the philologist Elwin Ransom through encounters involving other worlds, spiritual powers, scientific ambition, and the moral consequences of human choices.

Out of the Silent Planet was published in 1938, followed by Perelandra in 1943 and That Hideous Strength in 1945. The trilogy combines planetary romance with Christian philosophy and ideas drawn from medieval cosmology, mythology, and Lewis’s concerns about technocracy.

The books are sometimes called the Ransom Trilogy because Ransom is their principal human character. That informal name describes the series but is not its standard published title. The broader and canonical name is The Space Trilogy. Lewis’s friendship with J.R.R. Tolkien helped encourage both authors’ interest in imaginative fiction, though their approaches to science fiction and fantasy were different.