You Might Also Like: What Lies Beneath

Sometimes the strangest things on Earth...Are happening just below its surface. From tunnels carved by giant sloths to desperate attempts to stop the dead from rising again - these are the weird and wonderous tales of the sea beasts, hidden cities and impossible creatures that lurk beneath us.

Thank you to our experts who contributed to this episode: Austin Rogers, Sabina Magliocco, Greg Jackson, Brandy Shillace, Mitch Horowitz, Kathleen Tracy, Cord Whitaker, Don Wildman, Joseph Dituri, Rebecca Lieb, Hakeen Oluseyi, David Mizejewski, Sami Jarroush, Jason Horton, Ramy Romany, and Kavitha Davidson.

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