In this sequel to the hugely successful (and exceedingly cool) Walking With Dinosaurs, the series creators do what they admittedly wanted in the first place: to examine the development of mammal species after the dinosaurs' extinction. The average Joe on the street can likely pick a T. Rex or a Triceratops out of a line-up;  he would have a harder time identifying the Gastornis, a six foot-tall flightless bird of prey, or the Megatherium, an twelve-foot sloth that could kill a saber-toothed tiger with a single blow.

Presented as a series of six half-hour faux National Geographic documentaries combining real backgrounds, animatronic creatures and computer animation, Prehistoric Beasts shows us a world at once familiar and exotic.  Some episodes concentrate on creatures we know, like the Wooly Mammoth and Smilodon (the aforementioned Saber-tooth), even the Australopithecus, the upright-walking ancestors of the primate family. Others reveal a nightmare menagerie of land-roving, predatory whales and weird, huge animals that became evolutionary dead ends.

Unfortunately the CGI work isn't quite up to realistically depicting the necessary feathers and fur, but is incredibly good considering the budget, and doesn't detract from the total coolness of the project. There is more interactivity with the camera than there was in Dinosaurs, and bizarrely, at least one instance of bullet time. Add the stately narration by Kenneth Branagh, and you have an educational experience that doesn't feel like education.

Produced less than a year ago,  the elements are quite simply the best you could hope for. Flawless video, exciting audio.

With the series' six episodes filling the first disc, Disc Two packs all the extras, starting with the "Making Of" option. Don't expect lots of techno-jargon and behind-the-scenes footage here, though there is some; this is actually two more episodes, about 50 minutes each, under the original title "Walking With Beasts" - Triumph of the Beasts and The Beasts Within - that detail the scientific research that went into the series' creation. Long on history, short on production trivia. The first covers the mammals and the second the rise of man. Stick around through the end credits for some fun joke footage.

There are, additionally, a  largish photo gallery, six storyboard sequences, "Beast Files" with factsheets for the featured animals and a size comparison with a human figure; trailers for Walking With Dinosaurs, Allosaurus, the BBC America cable channel and Blue Planet, and a section of interviews with various production personnel, if the slightly misleading "Making Of…" wasn't enough for you.

Very, very cool - it leaves one hungry for more.