The creators of the Walking with Dinosaurs series that took the world by storm have returned to tell the story of Big Al. A few years ago, an amazing fossil was unearthed in Wyoming USA. Not only were the bones they found those of a dinosaur that lived 145 million years ago, the skeleton of this creature was very nearly complete. Now the scientists' find has been resurrected even more vividly as the BBC uses the same computer graphic and animatronic techniques as the original Walking with Dinosaurs series, to recreate Big Al's life for the television screen. In the first programme we follow him from his birth to his death - a 15-year story of a lone battle against formidable prey and voracious predators. The second programme is a scientific detective story to trace the evidence of Big Al. Employing the same state of the art graphic effects, Big Al roams modern-day museums and dig sites where we see passionate scientists explaining the research behind his tale.