1. [adj]  lying beneath what is revealed or avowed, especially being deliberately concealed; "subterranean motives for murder"; "looked too closely for an ulterior purpose in all knowledge"- Bertrand Russell
2. [adj]  being or operating under the surface of the earth; "subterranean passages"; "a subsurface flow of water"

Subterranean
A hand-picked team of scientists and specialists ventures deep beneath the Antarctic ice into a subterranean labyrinth that takes them into a perilous darkness toward an encounter with a terrifying mystery that is older than time itself. Original.

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