Part 1: New Blood

Time: 220 million years BCE

Place: "Arizona," on the Earth’s only continent of Pangaea

Actual Location Shots: New Caledonia

Cynodont, the missing link between reptiles and mammals, with a rat-like face and a dog-lizard body that has a little hair, is the poster child of this episode. Besides being somewhat cute, Cynodont mates for life, lays eggs but suckles its young, and the males hunt only at night. Best of all, it gets a pleasant woodwind-and-strings theme on the soundtrack.

The other primary characters of part 1 are Coelophysis, a light-boned, light green runner that resembles the raptors so familiar from "Jurassic Park" or the long-familiar Ornitholestes, who turns up in part 2; and Postosuchus, the real "heavy" of this episode (in both senses of the word)—20 feet long, heavy armor on back, massive jaw with slicing teeth, loud guttural cries and bellows, looks a little like a huge, skinny, upright crocodile that can rear up.

Walk-ons include Placerias, a large, lumbering herbivore headed for quick extinction; Plateosaurus, a 30-foot forerunner of the giant herbivores like Brontosaurus and Diplodocus; and Peteinosaurus, an early pterosaur. There’s an effective animatronic sequence of a Peteinosaurus drinking at water’s edge with its blunted yellow toucan face, and an animated sequence of a dragonfly getting nailed by the flying dinosaur, its wings crunching in Peteinosaurus’s mouth, then falling to the river surface to float away.

The episode has some bracing scenes. Pressed by predatory Coelophysis, a Cynodont pair eat their young and steal off in the night to survive another day. As the water supply dwindles during a dry summer, "cannibalism is common," we are told; and we glimpse animatronic closeups of a Coelophysis carcass with ripped head and neck, and another small one dangling from a live reptile’s mouth.