The Ballad of Big Al (broadcast in North America as Allosaurus: A Walking with Dinosaurs Special) is the first special in the Walking with Dinosaurs franchise. 145 million years ago an adolescent Allosaurus lay down to die in a dried up river bed. In 1991 scientists discovered his perfectly preserved body and nicknamed him Big Al. This is the story of this predatory dinosaur's life - how he grew from a tiny hatchling to the terror of the Jurassic plains, why his body was covered in so many wounds and how he ended up in the river bed.