Sir David Attenborough presents this landmark documentary which brings to life, in unprecedented detail, the lost world of the very last days of the dinosaurs. Searching in the hills of North Dakota, palaeontologist Robert DePalma makes an incredible discovery in a prehistoric graveyard known as Tanis - fossilised creatures, astonishingly well preserved like the bodies found at Pompeii. Whilst DePalma hunts for the evidence that can shed light on the final days of the dinosaurs, state-of-the-art VFX transports Sir David back in time to the Late Cretaceous to witness the creatures who lived at Tanis at the end of the Age of Dinosaurs. Meanwhile, cutting edge scanning techniques reveal fossilised secrets that could change our understanding of the dinosaurs' extinction once and for all.