A grim discovery in a Swedish lake reveals shocking ancient practices. Meanwhile, in the Canadian Arctic, the fossil of a previously unknown mammal is found.

Archaeologists in Russia find several mass graves, a World War II plane sits on a Canadian mountain, and cosmic rays in Antarctica stump experts.

Human remains are discovered high in the Ecuadorian Andes, while a strange earthquake-like event is investigated in Canada.

In Russia, 34,000-year-old graves are discovered. Meanwhile, a team attempts to locate a British World War II aeroplane that went missing in Iceland.

A mysterious volcanic island off the coast of Antarctica is explored, while the mummified remains of a teenage girl are found in the Peruvian Andes.

Mysterious industrial waste is discovered in an uninhabited part of Greenland. Meanwhile, strange mounds are found deep within the Arctic Circile.

A Kazakh farmer discovers ancient burial sites that may determine whether or not the legend of the Amazon women warriors is myth or reality. In the Italian Alps, a group of hikers explore long forgotten military infrastructure that points to the region's complicated and violent history. A shrine in the Indian Himalayas has long been said to be protected by supernatural powers, but strange markings on the temple reveal it was subject to an almost equally as powerful force. Palaeontologists discover a fossilized species unknown to science embedded in a rock hundreds of millions of years old.

A secret military base is discovered a few hundred miles from the North Pole. A man-made, ancient stone formation is found 120 feet below the surface of Lake Huron. A 1500 year old burial ground is discovered on the shores of the Baltic Sea. And in Russia's far east, a life-form that scientists think can live for thousands of years is discovered in the permafrost.

A giant naval vessel is located on the bottom of the Norwegian Sea. An ancient reptile-like creature unknown to science is found in the permafrost of Canada's Arctic. In Scotland, archaeologists are drawn to a strange, figure-eight shaped ditch. An Antarctic research base finds itself suddenly surrounded by blood soaked snow.