A group of hikers trekking across the Italian Alps stumble upon abandoned military infrastructure. What purpose did these camouflaged buildings serve?

Visits to the most remote, cold and inhospitable places on the planet to reveal great mysteries that have been frozen in time. This edition features a giant naval vessel located on the bottom of the Norwegian Sea and an ancient reptile-like creature found in the permafrost of Canada's Arctic. In Scotland, archaeologists are drawn to a strange, figure-eight shaped ditch, while an Antarctic research base finds itself suddenly surrounded by blood-soaked snow.