This graphics-intensive series takes viewers backwards through time to see what amazing extinct creatures stood, lived, fought and died in our backyards -- hundreds, thousands, even millions of years ago. Watch the modern sprawl of Los Angeles revert to farmland and settlements, desert, and then a lush green land prowled by woolly mammoths and saber-toothed tigers. Back even further, the land itself forms as two continental plates slam together in a violent upheaval. During the age of dinosaurs, pterodactyls circle the skies over an ancient ocean filled with sharp-toothed marine dinosaurs in search of their prehistoric prey. Each episode focuses on a different city: New York, D.C., Dallas, Los Angeles, Denver, and Chicago.