Opening with Disney's tried and true recipe of an orphaned character (take one dino egg, remove parents, and hatch), the only family Aladar (D.B. Sweeney) has known is the clan of lemurs who nurtured him from his egg to the three-ton iguanodon he is today. With no other dinosaurs on the island where they live, Aladar is content to play with his primate friends.
But Aladar's peaceful existence ends when a meteorite destroys their tiny island and changes the world forever. Forced to move to the ravaged mainland, Aladar and the four remaining lemurs join a large herd of desperate herbivorous dinosaurs searching for a reportedly glorious nesting area. Kron (Samuel Wright), the group leader, believes in the survival of the fittest, and consequently has little pity for elderly members like Baylene (Joan Plowright), a huge, slow brachiosaur or Eema (Della Reese) a tiring styrachosaur. Lingering at the back of the herd, they risk being eaten by predators.
This presents a difficult dilemma for Aladar, who has been raised with a teamwork philosophy. Yet encouraging Baylene and Eema to keep up with the others meets with criticism from the rest of the herd. As Aladar struggles with this ridicule and other challenges, his character grows, gains self-confidence and develops leadership skills. He even extends compassion toward an injured dinosaur that had previously rebuked him. And through Aladar's example the band of survivors learns a new way to live.
Unfortunately, these positive moments are often overshadowed by the tense and terrifying events of the action packed script. There's always a set of teeth, belonging to a carnivorous dinosaur, coming up from behind and the convincing nature of the highly detailed animation may scare young audience members to bits. Meanwhile, parents may feel like they've seen this story before, especially if they have a copy of Universal's Land Before Time on their video shelf. The scripts are alarmingly similar.
But whether it's a great valley or a nesting ground, this movie's greatest attraction is how it has evolved animation into a whole new species. Now if we could only hire a writer...