Air date: 2020-01-21

Runtime: 44 min

The desert town that faced a disaster of biblical proportions. Plus, vast coastal ruins that reveal a past once wiped from history.

Air date: 2020-01-28

Runtime: 44 min

The underground base with the power to destroy a nation, the site linked with an attempt to kill a dictator, and an ancient world discovered in the American wilderness.

Air date: 2020-02-04

Runtime: 44 min

Claustrophobic prison cells that contain a story worthy of international acclaim, and a vast mountainside complex that held the power to change the world.

Air date: 2020-02-11

Runtime: 44 min

A secretive underground base that concealed the power to destroy nations, and a sprawling industrial relic clinging to the edge of an unforgiving waterfall.

Air date: 2020-02-18

Runtime: 44 min

Including an exploration of a marooned iron-clad structure in Portland, off the coast of England, that hides a dramatic story of war and resilience; Pratt Cotton Gin Mill, a vast facility in the heart of America's deep south that helped tear apart a nation; and a Mediterranean island fortress at Spinalonga, Greece, that became the scene of a dark conspiracy.

Air date: 2020-02-25

Runtime: 44 min

Including an exploration of forgotten relics from the defence of America's homeland, at Fort Jackson, USA, concealed by the banks of the Mississippi River; a concrete behemoth at Lorient Sub Base, on the coast of France, that proved invulnerable to enemy bombardment; and a ghostly ruin at Gwrych that is now home to a haunting presence.

Air date: 2020-03-03

Runtime: 44 min

An American prison for the violent and deranged with links to an infamous cult leader, and a cavernous tunnel network in France offering shelter from unrelenting bombardment.

Air date: 2020-03-10

Runtime: 44 min

An Albanian village home to Allied secret agents, devastated for resisting the Nazi war machine, and a notorious asylum in America that enforced lobotomies on a terrifying scale.