Beginning in 1938, and later in 1943 and 1945, a few years prior to his publishing of the much better known Chronicles of Narnia series, Clive Staples (C.S.) Lewis published a trilogy of what is best called science fiction, starting with Out of the Silent Planet, in which an earthling, Elwin Ransom, travels to Mars, which is called Malacandra in the book. Following that, the book Perelandra was written; this time, set on the planet Venus...and finally, That Hideous Strength ends the trilogy and is set on our home planet, Earth.

According to a letter, he was influenced to write this trilogy in part from HG Wells' First Men in the Moon, which was first published in 1901, and also by David Lindsay's A Voyage to Arcturus, which was published in 1920.

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