Perelandra

Also wonderful on audio (Audible | LibroFM).

FROM THE PUBLISHER: 

In Perelandra, Dr. Ransom is recruited by the denizens of Malacandra, befriended in Out of the Silent Planet, to rescue the peace-loving planet Perelandra (Venus) from a terrible threat: a malevolent being from another world who strives to create a new world order, and who must destroy an old and beautiful civilization to do so.

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