Series from 2014
Rob Bell explores Britain's subterranean world, from natural and man-made caverns to the cold war government and everything in between.
In Scotland, Rob Bell discovers the gruesome secrets of an ancient cave.
In London, Rob discovers a labyrinth of tunnels the general public is not meant to know about.
Rob explores a mile of caves and one of Britain's deepest potholes.
Rob Bell visits Europe's largest cave system underneath Brecon Beacon national park.
Rob discovers a long-lost secret when he visits the ruins of Nottingham castle.
Rob explores a mystical cave system that altered Victorian Britain's view of human history.