If you're a paleontology buff, this series is for you. And the fun-loving Nigel Marvin provides a great narrative. Explore the prehistoric world in search of sea-based monsters. It focuses on life in ancient oceans during each prehistoric period. Nothing, not the carnivorous dinosaurs of the past, nor the imagined sea serpents and monsters of maritime history, nor the great white shark, salt water crocodile, killer whale and leopard seal of today can compare to the horrifying hunters of the prehistoric oceans.

The Basilosaurus, the first of the large whale species, is not a harmless plankton eater but a fearsome high speed hunter. And most frightening of all is the Megalodon, a gargantuan ancestor of the great white that makes its modern day relative look like a tuna.

A Winning Design clarifies what makes a mammal different from reptiles and birds. No, it isn't egg-laying: both the platypus and the echidna are egg-laying mammals; it's their ability to adapt. And it's this adaptability that becomes the crux of the remainder of the series. From the tiniest bat to the massive blue whale, all mammals share the ability to nurture their young on milk and regulate their own temperatures.

The idea of intelligence is explored in the concepts of computers (using bits as their basic units of information), whales (in their songs and their disruptions by human activities), DNA, the human brain (the evolution of the brain stem, frontal lobes, neurons, cerebral hemispheres, and corpus callosum under the Triune Brain Model), and man-made structures for collective intelligence (cities, libraries, books, computers, and satellites). The episode ends with speculation on alien intelligence and the information conveyed on the Voyager Golden Record.

The series takes place after the extinction of the dinosaurs 65 million years ago and recreates animals of the Cenozoic with computer-generated imagery and animatronics. The first episode starts 49 million years ago, when Earth has fully recovered from the dinosaur extinction and is covered in a mysterious forest. This is a time that the world has almost forgotten - Germany was a hot sweaty jungle, birds ruled the earth and preyed on miniature horses and whales walked on land.

Moving on to the Late Eocene period 36 million years ago and mammals have prospered and are now the largest creatures on land and sea. This is an era of animals like andrewsarchus, the biggest mammal carnivore ever to walk on land, and the brontotheres, small-brained herbivores. It is in the sea, however, that the most monstrous mammals of all can be found. We follow the fate of a female basilosaurus, a huge serpent-like early whale, but nothing like the gentle filter feeding whales of the 21st century. Four times the length of the great white shark, with jaws to match, she is every inch a killer.