When the Earth was young, long before the plates had separated, before Atlantis and Mu sank, alien intelligences of incomprehensible power were cast from their home worlds and imprisoned across space by unknown forces. At least five of these entities are imprisoned here on Earth, waiting for the alignment of certain heavenly bodies, for some tectonic upheaval, or for the fumbling explorations of humanity to free them. So say the works of H.P. Lovecraft, Clark Ashton Smith, Lin Carter, Brian Lumley, and ot hers, at any rate.
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