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

The third novel in C.S. Lewis’s Space Trilogy is That Hideous Strength.

Published in 1945, That Hideous Strength follows Out of the Silent Planet and Perelandra. Unlike the first two novels, which focus heavily on journeys to other planets, the third book is set mainly on Earth and combines science fiction with academic satire, Christian themes, and Arthurian elements.

The story centers on Mark Studdock and Jane Studdock, whose lives become entangled with the National Institute of Coordinated Experiments, or NICE. The organization presents itself as a force for scientific and social progress while pursuing increasingly disturbing goals.

The title echoes a line from David Lindsay’s 1920 novel A Voyage to Arcturus, which Lewis admired. Readers sometimes identify The Dark Tower as the trilogy’s third volume, but that is an unfinished and posthumously published Lewis fragment, not the completed third novel.