An earthquake devastates Los Angeles, allowing thousands of dinosaurs to escape from a huge dinosaur zoo near there. They invade the city and battle the armed forces. A mean and tough general is in command, working with a zoo director who is a scientist. Bombs are dropped on the city as warplanes and tanks battle dinosaurs. Huge plant-eaters stampede, crushing people. Meat-eaters rip people apart as troops shoot dinosaurs with automatic weapons, people panic, killing others in traffic.