Synopsis: Noby and his friends decide to build a secret hideout in an underground cave. In the depths of the cave, Sneech comes across a shocking sight. Unable to believe his eyes, he returns the next day with a video camera in hand, only to lose his way after a surprise encounter with the RC plane he lost in the river. The rest of the gang return home, not knowing that Sneech is still in the cave. When they realize what they have done, it’s too late: the “Anywhere Hole” is broken, and Sneech is trapped! Using Sneech’s video camera as a clue, Noby and his friends discover a hole at the bottom of the river that leads to their secret cave. As they search for Sneech, they are led to a huge subterranean world where dinosaurs roam. Can Noby and the gang find their friend? The sensational eighth tale of the Doraemon’s Long Tales series!