While trying to obtain "Tree Sweets", Littlefoot into the tree and knocks down all the blossoms, which attract the tiny dinosaurs, Tinysauruses. They devour the plants and disappear. But Littlefoot isn't blamed for the disappearance. Instead of taking the blame, he accidentally makes the adults go into a "Get Frankenstein" frenzy when they believe the tiny dinosaurs were the main cause. Now Littlefoot and his friends must protect the tiny herd, and in the end learn the value of honesty.

When the dinosaur families get trapped in a valley by an ice storm, one family of "spike tail" dinosaurs volunteers to leave since they consume more food than the others. Meanwhile, the young dinos and a new adult dinosaur named Mr. Thicknose, head out to bring back their friend Spike, who has left his friends to be with members of his own species.