Planet Dinosaur

In prehistoric North Africa, the carcharodontosaurus, a lizard-like carnivore with shark-like teeth more than six inches long, and the spinosaurus - at four metres, one of the biggest killers to walk the planet - once battled for supremacy.

A look at the last of the killer dinosaurs - carnivores that took killing to a new level. By the end of the Cretaceous period - 75 million years ago - these gigantic and specialised hunter-killers had spread throughout the globe. In the southern continents, it was the powerful and muscular abelisaurids that reigned supreme, but it was the famous tyrannosaurids (or tyrant dinosaurs) that dominated in the north.

This episode focuses on the new giants, the heavyweights of the dinosaur world. It is only in recent years that experts have unearthed the biggest dinosaurs that ever lived.