The story begins when Jack comes to an amusement park to ride a new attraction called “Tunnel of Destiny”. When he enters the tunnel in a railcar, everything goes wrong! The railcar stops in the darkness. Jack runs out of patience and begins to press all buttons and levers, trying to move it. Suddenly the railcar dashes out of the tunnel, falling down into a deep lake. Shocked, Jack sees shaggy members of a primitive tribe. It is a real time travel!