A young boy travels with his violent and alcoholic father to bring back his mother, who has run away from home due to his abuse.

An aging, booze-addled father makes the trip from Montana to Nebraska with his estranged son in order to claim a million-dollar Mega Sweepstakes Marketing prize.

The story revolves around sub-zero heroes: a woolly mammoth, a saber-toothed tiger, a sloth and a prehistoric combination of a squirrel and rat, known as Scrat.