Tom believes other people might be in the Land of the Lost and discovers Christa, the jungle girl. She helps find an antidote to save Tom after a poisonous lizard bites him.
The Porter family goes searching with Tasha to find a way home. Unfortunately, they run into creatures called Sleestak and their leader, Shung. The Sleestak steals the family car and captures Tasha.
The alignment of the three moons causes the Land of the Lost inhabitants to act strangely, including Stink and Tasha. They Stampede towards the Valley of Death. Meanwhile, Christa and the Porters race to save their friends from death.
Annie finds Shung's magic crystal sword, which gives her powers she never dreamed of. However, its evil nature slowly changes her for the worse, and she begins acting like Shung.
Annie's pet dinosaur, Tasha, gets in trouble once too often, so Tom decides she should be returned to the jungle to fend for herself.
