One day, a shower of flying rocks impacts near the Great Valley and causes a rock slide in the Mysterious Beyond, which blocks the water supply of the Great Valley. The increasing lack of water causes conflicts between the inhabitants of the Great Valley, who have lived in relative peace and harmony until this event.
When the inter-species situation becomes worse and worse, Littlefoot and the others set out to find water to keep the peace in the Great Valley. They are pursued by an evil trio of teenage dinosaurs who constantly bully Littlefoot and his friends and plot to take over the Valley. Their names are Hyp, an ill-tempered Hypsilophodon (the leader of the trio and the "Littlefoot" of his trio), Mutt, a clumsy Muttaburrasaurus (Hyp's assistant and the "Cera and Petrie" of the trio), and Nod, a cowardly Nodosaurus (Hyp's thug and the "Ducky and Spike" of the trio). When Littlefoot and the others find a small lake, the trio emerges and claims the waterhole for themselves, demanding that Littlefoot and the others keep silent about their discovery. Unwilling to comply, Littlefoot and the others flee from the bullies. During the pursuit, the bullies are chased away by a wasp, and the children discover the reason behind the blockage of the Great Valley's water source.
Before they can return and tell the other Valley inhabitants the truth, lightning strikes a tree and ignites a wildfire that spreads rapidly throughout the dried Valley. The dinosaurs barely make it to safety at the edge of the Mysterious Beyond. When the children tell the adults of their discovery, disagreements about what to do erupts among the adults, preventing them from doing anything to utilize this knowledge. Hyp, Nod, and Mutt set out into the Mysterious Beyond on their own to get to the water first.
Anticipating the danger, Hyp and his cohorts have gotten into recognizing commonality with them, Littlefoot and the others follow to help if necessary. It becomes so when Hyp jumps into a tar pit; after mistaking it for water. He calls for help, but Mutt and Nod do not save him. Instead, they argue about which one of them must save him. But Littlefoot cuts in, and tells Mutt and Nod that Hyp is stuck in the tar pit. Then, he hatches a plan to pull Hyp out. Finally, Littlefoot and the others pull him out of the tar. Soon afterwards, the adults appear in search of their children, and are finally united by the understanding that it was the unity of their children that helped them find water. It is implied during the discussion that Hyp's own experience of harsh treatment by his father is the cause of his harshness toward others.
Before they are able to take further steps, the herd is attacked by a pack of four Velociraptors. The pursuit leads to a dam of boulders created by the rock slide that has blocked the Valley's water supply. As the Sharpteeth and the adults battle, the children, including Hyp and his cronies, work together to break the dam. They all watch as the freed water and it washes away the Sharpteeth. The water also puts out the fires which are still burning in the Valley. Finally, they manage to survive and land on the opposite bank. Now the herd is able to return to the Great Valley.
The herd returns to the Valley, which now has enough water for them. However, the fire has destroyed most of their green food. Working together, the dinosaurs wait for the plants to regrow, feeding on the remainder proportionately by moving from one verdant area to another and sharing everything they find. This pattern results in the event being called "The Time of the Great Giving."
Sound Effects Used
- Sound Ideas, CARTOON, LAUGHTER - CHIPMUNK LAUGH, HUMAN (heard once in the Universal Cartoon Studios logo)