Episode 1

Graham visits Gunung Padang, an Indonesian archeological site, to find proof of a lost civilization — and the potential cataclysm that wiped it out.

Episode 2

In Cholula, Mexico's oldest continuously-inhabited city, the journalist inspects the world's largest pyramid for signs of a forgotten past.

Episode 3

Graham discovers a fascinating pattern that may connect the spectacular megalithic temples of Malta, which he believes to be much older than reported.

Episode 4

Few scholars have investigated the Bimini rock formation off the coast of Miami, once fabled to be the road to Atlantis — but Graham dives right in.

Episode 5

At Göbekli Tepe, the oldest known megalith in the world, Graham questions if simple hunter-gatherers alone could have built such an advanced structure.

Episode 6

Graham visits ancient mounds in North America and wonders if they contain astronomical significance — or even warnings of an apocalyptic climate event.

Episode 7

The author returns to Turkey to explore Derinkuyu, an ancient underground city and survival bunker that could shelter thousands in times of crisis.

Episode 8

In the ancient geological sites of North America, Graham envisions an apocalyptic event that may have changed the Earth — and its inhabitants — forever.