"Ice Age" is about a group of prehistoric animals - Manny the Mammoth, Sid the Sloth and Diego the Saber-tooth Tiger who are traveling to warmer lands, in preparation for the coming ice age. They were originally traveling with their own species groups before circumstances lead to their making the journey together. Along the way they pick up a human child and, at Manny’s insistence, are attempting to return it to its family. The only problem is that Diego’s leader, Soto, wants the baby, and a plan is hatched in which Diego will deliver the child, and his traveling companions, to the rest of the pack. The mismatched traveling party, including the baby, known only as “Pinky”, has trouble getting along a first, but through a series of adventures, end up becoming, first reluctant, then accepting, friends. They eventually have a showdown with Soto and his minions, and Diego must decide whether his loyalties lie with his old or new pack.