Gigantic and menacing, the Tyrannosaurus Rex is probably the most famous dinosaur that ever lived. However, new discoveries are proving wrong the previous depiction of the T.Rex as dull and slow - in fact, he was complex, dynamic and even bird-like. We get up a close and personal look at how they lived, from nesting in pairs to caring for their young and how they played together. The reign of the T.Rex ended when the impact of a huge asteroid hurtling toward Earth decimated the dinosaur population — but not all dinosaurs died. A few survivors such as Troodon, a small, bird-like dinosaur and the smartest dinosaur to ever live, may have hung on, yet eventually it, too, succumbed to the catastrophe. Watch as a lone Troodon — "the last dinosaur" — struggles to survive in a post-apocalyptic world. But our Troodon may not really be the last dinosaur. If birds are their descendants, then we're still living in the Age of Dinosaurs — and the DINOSAUR REVOLUTION continues.