The huge Titanosaurs break out of their compound and cause chaos just as Nigel is leaving on an expedition to prehistoric South America in search of the legendary saber-toothed cats. He locates them, but only after almost colliding with a herd of hippo-like Toxodon in his jeep. A giant terror bird is attacked by one of the saber-toothed cats and Nigel takes pity on it, luring it back to the safety of the park.

Big cat expert Saba Douglas-Hamilton accompanies Nigel back to South America to rescue saber-toothed cats as they face extinction. Despite dangerous encounters, they succeed — but not soon enough to save the life of a saber-tooth cub.

Back at the park, there's better news when the Ornithomimus eggs hatch and the park has its first babies.