During the Cretaceous Period, a dinosaur named Patchi (Justin Long) hatches among a herd of Pachyrhinosaurus in Walking With Dinosaurs: The 3D Movie 3D + 2D Blu-ray + DVD set.

Patchi's runt status means he must use his wits rather than strength to compete for food with his larger brothers and sisters, particularly Scowler. After a terrible fire leaves Patchi, Scowler, and a female named Juniper on their own, the rivalry between the brothers escalates to a dangerous level. Patchi must summon his inner courage and strength to become the leader he was born to be.

Patchi and his siblings Scowler and Juniper are born into the dangerous world of the Cretaceous period, where predators such as Gorgon the Gorgosaurus would be only too happy to make a meal of them. Can Patchi make it to adulthood and overcome the many hurdles required to become herd leader?