A vanished Neolithic structure in an Irish farmer's field, an ancient oasis in the remote reaches of a Chinese desert, a centuries-old buried treasure in the U.K. and a dreaded predator in the Pacific Ocean are discovered by accident using drones.

Unlock military secrets from the air; spot a Nazi weapon designed to turn the tides of war in France; a covert Russian military tower in Chernobyl's shadow; a rumoured nuclear lab buried in Australia; a hush-hush surprise underneath Alcatraz.

Over a hundred big concrete arrows scattered across the U.S.; a giant chalk figure with an oversized phallus on an English hillside; a mysterious hole in the middle of a lake in Southern California.

A Turkish drought reveals a long-lost ancient Basilica and its secrets; a church spire punches through the surface of a toxic sludge in Romania; the hull of a massive ship in the North Sea answers decades old questions.

Nubian pyramids reveal the rise of female power in Ancient Kush; a shocking satellite image uncovers secrets of an ancient ancestral Puebloan site in New Mexico.

Strange markings in the remote reaches of Northern Finland; drones find a Manhattan-sized mystery in the depths of a Vietnamese cave; secrets are no longer hidden in the Antarctic; a lost sky-high world in Mozambique gets a visit from above.