While Scrat the Saber-toothed Squirrel is still trying to find his precious acorn, the misfit trio of Manny the Mammoth, Sid the Sloth and Diego the Sabre-tooth Tiger have settled down in an isolated valley with numerous other animals. However, the trio soon discover that the ice wall surrounding the valley is barely holding back a massive body of water behind it and the melting state threatens to break the wall and flood the valley. With their one chance of survival being a boat at the other end of the valley, the trio make a desperate exodus there. Along the way, they meet Ellie, a female mammoth who is convinced that she is an opossum like her brothers. While the strange group continues their trek across the valley, they must learn to get along. Manny struggles to find some connection to Ellie, who may be the only other one of his kind.

Special features: "No time for nuts": an all new Scrat short; All new Crash & Eddie stunts - 3 short shorts; Crash and Eddie blooper; Commentaries by director Carlos Saldanha, producer Lori Forte and the production team; The animation director's chair including storyboard, animation, finals from "Play dead," "Fish story," "Nuts," "Family," "Face off," and "Drain"; Introduction to new characters featurettes: "Meet Ellie" and "Meet Crash and Eddie"; Lost historical films on the Ice Age period: The Sloth "Nature's lovable lisper," The wooly mammoth "Nature's beast of burden," The saber-tooth squirrel "Nature's nutty buddy," The saber-tooth tiger "Nature's fearsome feline," The vulture "Nature's cleaners," The possum "Nature's spunky spectacles"; Sloth dancing to Sid's sing-a-long; Set top games include "Factoid meltdown", "Scrat's piranha smackdown," "Sid soccer game," "Personality match game" and Vivendi Universal game memory challenge; "Silly Sid and John Leguizamo" featurette; Marketing of 'Ice Age': Scrat on 'Family guy' footage, Sid hosting 'Domination Line up'; Inside look on "Simpsons, the movie"; Cross promo trailers; DVD-ROM content contains link to website games.