After a visit to the La Brea Tar Pits at the Page Museum, a group of teenagers accidentally come across a gigantic, preserved, half-buried egg while escaping another local gang. A dinosaur hatches from the egg and the group: Jeremy, Mario, Shades and Wally befriend him, naming him Denver. The gang has to keep him away from various nefarious individuals, like greedy business man and rock-band manager Wilson Fizzback, who sees the dinosaur marvel as a way of getting a quick buck. Yet keeping the dinosaur out of sight, is easier said than done.