Stephen tells the 180-million-year story of dinosaurs, travelling back in time via amazing computer-generated worlds. In this edition he encounters the Diplodocus and the Allosaurus.

Stephen finds himself in the Early Cretaceous period, 125 million years ago - the era that saw an explosion in dinosaur diversity - and encounters the terrifying Utahraptors.

Stephen lands in a huge forest 68 million years ago - in the Late Cretaceous period - home to the deadliest of all dinosaur predators: the cunning hunter and terrifying scavenger T-rex.

Stephen goes back 66 million years to witness the apocalyptic end of dinosaur life