What is the title of the final novel in C.S. Lewis’s Space Trilogy?

That Hideous Strength is the final novel in C.S. Lewis’s Space Trilogy. It was published in 1945, after Out of the Silent Planet in 1938 and Perelandra in 1943. The trilogy’s recurring protagonist is Elwin Ransom, although That Hideous Strength places greater emphasis on Mark and Jane Studdock.

Unlike the first two books, the final novel is set mainly on Earth. Its plot centers on the National Institute of Coordinated Experiments, or N.I.C.E., an organization whose scientific and political ambitions threaten human freedom. Lewis uses the story to examine technocracy, propaganda, marriage, and the danger of treating human beings as material to be engineered.

The title comes from a line in David Lyndsay’s sixteenth-century poem Ane Dialog. The Dark Tower is another Lewis work, but it is an unfinished science-fiction fragment rather than the concluding novel of the Space Trilogy.