Thanks to the ingenious engineering of Cyrus Smith (Gerard Tichy), on the uninhabited island in the Pacific - hundreds of miles from any shipping route - they can make the bare necessities for the small group of stranded people. They have learned to hunt, fish and find edible plants. With a burning glass made from two watch glasses filled with water, they succeed in making a fire and with a Jacob's staff they determine the position of the remote island. There the young Harbert has an encounter while hunting, which could become the key of the inexplicable appearances of this island. They come to a mountain that makes it impossible to get there.