volcanic shelf. The submarine then surfaces to find itself in a tropical lake surrounded by steep cliffs. They have traveled through deep underwater caverns and have surfaced in the cauldron of an extinct volcano. The crew soon discover that dinosaurs exist on the island and promptly escape from a stampede of Brontosaurus. Later on shore, the Chilean crew are attacked by a prehistoric rhinoceros-like mammal known as an Arsinoitherium while trying to cross a log bridge. The Arsinoitherium gores many of the sailors to death, before knocking the fleeing sailors from the log bridge into the raging river below; weak with horror, Steve stumbles through the jungle back to the others and just avoids been killed by a bull woolly mammoth. The survivors, assuming that they will never see civilization again, build a shelter to live in on a high cliff over looking the lush valley. After Ned Hallet shoots a Brontosaurus, the sauropod retaliates by destroying one of the shelters with its long neck, and it is Elaine that saves everyone by striking a burning torch into the beast's mouth. Everyone is furious with Hallet for putting them in danger; Hallet leaves the camp in anger after being scolded and takes his frustration out on a baby Triceratops. Its mother rushes to the aid of the dying infant and gores Hallet to death. Steve then takes command over the group and decides to repair the radio from the sub, but needs a replacement leyden jar for it to work. While the survivors are exploring ancient ruins, looking for a replacement leyden jar, a block gives way, causing Elaine to fall. Elaine is attacked by a Pteranodon which is driven off by Steve. Shortly afterwards, the crew are chased into a temple by an aggressive Stegosaurus. The crew is then trapped between the Stegosaurus and a Tyrannosaurus which lives in the temple. Rather than killing the crew, the two dinosaurs fight one another. In the end, the Tyrannosaurus kills the Stegosaurus and feeds it to its infant as the crew escapes. After searching the temple, the crew discover a type of metal jar which they could use to get their radio working. The crew try to send out an S.O.S., but the volcano begins to erupt, causing mass hysteria among the dinosaurs and other prehistoric animals. A Pteranodon crashes into the tower used to conduct the signal, leaving the crew