Littlefoot and his friends are constantly being bullied and browbeaten by three teenage dinosaurs: Hyp, a Hypsilophodon; Nod, a Nodosaurus; and Mutt, a Muttaburrasaurus. However, when a shower of meteorites (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, Hyp, Nod, and Mutt are no longer the biggest worry of Littlefoot and his friends. 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.