From Greek fire to Roman concrete modern humans are only now beginning to rediscover the secret technology of the ancient world.

For centuries Damascus steel was legendary, and the crafting of this superb metal a closely-guarded secret. So what happened? Has anyone cracked the code on the lost techniques of forging Damascus steel?

The Baghdad batteries and the Antikythera mechanism have puzzled many historians -- they just appear too advanced for their time. Where did they come from?

In the 1960s, UN Security Chief Dag Hammarskjöld died in a plane crash over modern-day Zambia. For decades the files on the crash were classified or suppressed -- and now, it seems, the truth is finally coming to light.

For decades Fidel Castro ruled Cuba -- and the CIA continuously tried to assassinate him. Some of their plans seemed orthodox, but others were outrageous (and even involved organized crime).

Could ebola really become a global epidemic, or is it a matter of sensationalism and manipulative journalism?

From bananas to Tasmanian devils, diseases may make entire life forms extinct. So what about humans?

Pope John Paul I was one of the shortest-reigning popes in Church history, and his untimely death led to numerous conspiracy theories. But could any of them be true? Why do some people believe this pope was murdered? Tune in to learn more.

Unmanned aerial vehicles (UAVs) have changed the nature of war. But where are they flying, and what are they doing? The answers might surprise you. Tune in to learn the Stuff They Don't Want You To Know about drones in the second part of this series.

Unmanned Aerial Vehicles, or UAVs, have fundamentally changed the nature of warfare. But who controls them? What are they doing, and why? Tune in to learn more Stuff They Don't Want You To Know about drones.