It is the mid-Triassic period, an the sun is setting on the age of reptiles. Once the most dominant lifeform on the planet, reptiles are now represented by only a few species. But as the age of reptiles wanes, new animals are on the rise, and among them, the first members of a new dynasty: the dinosaurs.

It is the late Jurassic, and dinosaurs rule the land. At the height of this reign, sauropods are the dominate herbivore on Earth. We follow the life of one sauropod, a Diplodocus, from hatchling to sub-adult, and the challenges she faces in her world.

Dinosaurs may rule the land, but it's a different story in the oceans. Marine reptiles dominate the seas. A school of female Opthalmasaurus are moving into the reefs around the northern Tethys Sea to give birth. Once born, the young ichthyosaurs must dodge sharks, plesiosaurs like Cryptoclydus, and the monsterous pliosaur Liopleurodon, the largest carnivore ever.

Reptiles not only rule the seas, but the skies as well. This is the time of the pterosaurs, flying reptiles that dominate the Cretaceous skies. And at this point, none is as large as the massive Ornithocheirus, the largest pterosaur at the time. We follow the final days of one such Ornithocheirus as he makes his way to the mating grounds, soaring over the lands ruled by dinosaurs.

In the mid-Cretaceous, Australia, Antarctica, and South America are still connected in one super continent. This is a time when the South Pole is a huge polar forest, where for five months of the year, the sun never sets. The Antarctic forests are a land which time forgot, where allosaurs still prowl the forests and ancient amphibians still hunt along the river banks. We fellow a year in the life of a clan of small dinosaurs, Leaellynsaura, and their struggle to survive in this unique environment.

The year is 65.5 million BC, and the time is 11:59pm for the dinosaurs. Volcanic activity has begun to choke the land, and dinosaurs are suffering. Few eggs are hatching, poisoned by the toxins in the air. Dinosaurs are on the decline, while mammals are thriving. The pterosaurs are all but gone, replaced by birds, and a massive asteroid is on its final journey to Earth. In this world, the most infamous carnivore stalks the land, the mighty Tyrannosaurus.

The short, hard life of a single Allosaurus is followed through his entire six to seven year life. Life for Al starts within a single egg, but even with mom around, it ain't easy being a little preadator. Al's adventures get more exciting as he grows, including a dramatic hunt of Diplodocus. Al is well on his way to becoming top dino in his world - until a fateful accident stops him cold

Zoologist and adventurer Nigel Marven travels back in time on a prehistoric safari to find some of the most spectacular animals ever to live. On this adventure, Nigel travels to Cretaceous Mongolia to track down Therizinosaurus, a dinosaur with monstrous claws and an arm as long as a man is tall. While he tracks down this elusive "carnivore", Nigel meets a varity of dinosaurs that lived in this unique habitat, including some that even Nigel wants to avoid! When Nigel finally does encounter Therizinosaurus, it's nothing like he expected, and he has a close encounter with the "saurian" kind.

Zoologist and adventurer Nigel Marven travels back in time on a prehistoric safari to find some of the most spectacular animals ever to live. This time Nigel has traveled back 100 million years to Cretaceous South America, during the true time of the titans. Nigel is on the trail of the largest land animal ever to exist and manages to run into the biggest predator to ever stomp the land. Dodging giant, aggressive crocodiles, Nigel looks to capture the ultimate hunt.

Nigel Marven searches the ancient seas for the most vicious animals to ever prowl the oceans. His first stop is the Ordovician, where he battles sea scorpions and encounters the giant orthocones. Next stop is the Triassic, where he tangles with Nothosaurs and must fend off the giant icthyosaur Cymbospondylus. His next stop could be his last, for he faces off with the armored fish Dunkleosteus.

Nigel Marven continues to search the ancient oceans for the deadliest sea monsters of all time. He must travel to the Eocene, 36 million years ago, and come face to face to the killer whale Basilosaurus. His next mission will take him to 4 million years in the past to tag the monster shark Megalodon, a shark that makes the Great White look like a minnow in comparison! But that's only if he survives his encounter with Dunkleosteus, the monster armored fish.

Nigel Marven continues his adventures in the ancient past. Diving into the Jurassic sea, Nigel risks life and limb literally against a pair of Liopleurodon, the massive pliosaur that dominated the Jurassic oceans. Nigel then travels to "Hell's Aquarium", the shallow sea that covered the American mid-west during the Cretaceous era. Here, he comes face to face with the monster mosasaurs, huge carnviourus reptiles with nasty attitudes. Of course, that's only if he survived his close encounter with the giant shark Megalodon.