Summary In the southwestern Pacific Ocean, a mythical volcanic island called Kolombagara rises out of the sea. Among the palm trees, a cave is found to contain curious items - boots, a helmet and a broken bowl. It becomes clear that this cave was not formed by nature, but rather is the result of human labor. Who trekked through the dense jungle to dig a tunnel here? The Vu Quang Nature Reserve sits in the Annamite Mountains on Vietnam's north central coast. A surveyor conducting research in the region discovers two long, slender trophy horns and two skulls from an unknown animal. What animal do these skulls and unique horns belong to? The immense Rising Star Cave complex in South Africa is a labyrinth of passageways, chambers, tunnels and underground rivers. Some areas of the cave system are nearly impossible to access, which is why researchers exploring the complex are shocked to find bones in a tiny crevice off of an extremely narrow chamber. Who do these bones belong to and how did they get here? Near the town of Port Kaituma in northern Guyana, backpacking tourists stumble on a rusted-out crane truck deep in the jungle. The strange truck is knocked on its side, blanketed in vines and appears to have been looted for metal and parts long ago. How did this truck end up here?

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