RJ Williams the raccoon (Bruce Willis), is a raccoon who lives in Tucson Arizona USA, while foraging for food, encounters the hibernating bear Vincent (Nick Nolte), and his large cache of commercially-packaged food. RJ tries to steal it, but instead wakes Vincent and causes the food to be crushed by a truck on a nearby road. Fearful of being eaten by Vincent, RJ promises to restore the cache within the week when Vincent has fully awakened from hibernation. RJ finds a nearby suburban community that has been recently erected, and a small forested plot where a pack of hibernating animals have just awoken, surprised to find a large hedge that separates the forest from the human community. Verne the box turtle (Garry Shandling), the group’s elder, urges the others to start stashing food for next year. RJ appears to the group and tells them they can collect all the food they will need within a week by raiding the humans’ trash and homes. Verne is extremely pessimistic about crossing the hedge, but RJ is able to convince the others to join him.
Initially, the animals only raid for food at night, but RJ realizes he needs to work faster to restore Vincent’s cache, and organizes daring daytime stunts, such as having the opossum, Ozzie (William Shatner), feign being run over by a car allowing the other animals to steal food from it. Verne becomes extremely annoyed at RJ putting his “family” in danger. Meanwhile, Gladys Sharp (Allison Janney), the president of the development’s homeowner association, realizes they have a vermin problem, and calls for help from Dwayne LaFontant (Thomas Haden Church), aka “The Verminator”. Dwayne installs a high-powered extermination system in Sharp’s backyard.
After one raid, RJ is surprised that the other animals now consider him part of their family, and provide him with a luxurious spot using items they’ve stolen from homes. RJ feels guilt over using the animals and attempts to tell the truth to Verne, but cannot do so. Meanwhile, Verne, still worried about his family’s safety, attempts to return all the stolen food to the humans; RJ finds out and tries to stop him, but the wagon the food is on is dragged by a playful rottweiler named Nugent (Brian Stepanek) and eventually is destroyed. The other animals upon learning, are angry at Verne, who tries to convince them of RJ’s manipulation, and accidentally makes a remark which convinces the animals he values himself above the rest of them.