RJ, a raccoon, is foraging for snacks in a vending machine. When that attempt fails, he sneaks into the cave of a bear named Vincent to steal his large cache of food. Giving in to temptation and stealing everything, RJ suddenly wakes Vincent up by opening a can of "Spuddies potato chips." The food and the wagon it was on are inadvertently destroyed by a passing truck. To save himself, RJ offers to get the food and the wagon back for Vincent, and therefore has until the next full moon to do this in before the bear wakes up from his hibernation, and will kill RJ in case of transgression. Desperate for help, RJ finds an advertisement for a residential community and is inspired by that to get the food back.
Meanwhile, a group of foraging animals wake up from their hibernation. Led by the tentative turtle Verne, the animals include the hyperactive squirrel Hammy, the attitude-stricken skunk Stella, the porcupines Penny and Lou, along with their triplet sons, Spike, Bucky and Quillo, and the opossum Ozzie and his daughter Heather. While foraging, they encounter a hedge that separates them from the human community beyond the now-small forest, mistaking it for a monster; their confusion and lifestyle of foraging gives RJ an idea to use them to retrieve the goods he needs to appease Vincent. He quickly warms up to the group, convincing them about the "wonders" of human kind and the ease of stealing and gathering food from them. All of the animals accept, except for Verne, who is wary of RJ after encountering some of the humans and after homeowner and HOA chairman Gladys Sharp frightens them off her porch during their first venture out into the neighborhood. However, the others ignore his warnings for the more enthusiastic and charismatic RJ. After several incidents of their food theft, Gladys calls in an eccentric exterminator named Dwayne LaFontant, which Verne discovers after an incident during which RJ disguises Hammy as a rabid squirrel to steal cookies and a red wagon from two girl scouts. Frustrated with RJ's influence, Verne attempts to return the food, resulting in an argument between him and RJ, which excites a neighborhood rottweiler named Nugent, all of which results in the obliteration and total destruction of their food supplies. Verne, inadvertently insults his friends while trying to defend his actions; hence, the others turn their backs on him and restore their faith in RJ, who deep inside regrets his actions.
Before RJ can tell Verne of his real plans, he gets the idea of getting all of their supplies back by robbing Gladys' house as she prepares for a big party. Using Stella to lure her cat Tiger away, the others break in to steal the food, but they are caught when Gladys wakes up and finds them in her kitchen. Chaos ensues during which RJ inadvertently reveals the true purpose of his plans when he's getting a can of "Spuddies". The raccoon goes to return the food to Vincent, leaving the others to be caged and captured by Dwayne. But when RJ compares Vincent's methods to his own, he realizes that he's got real friends and a true family, and should not be like the bear; therefore, he steals the food wagon, destroying the supplies again – which angers Vincent – and goes to rescue the others, the commotion causing Dwayne to be knocked out and the animals to take over the van. The ensuing chaos returns the party to Gladys' house and they destroy the house; so she, Dwayne and Vincent trap all the animals inside the hedge. Hammy is given an energy drink, which brings him to move faster than the speed of light in which he triggers an illegal trap called a Depelter Turbo Dwayne set up with Gladys' permission, trapping the humans and Vincent in it. The police arrive and arrest Gladys for having the Depelter Turbo in her yard and cage Vincent to be sent to the Rocky Mountains. As for Dwayne, he also gets arrested but manages to escape. However, he comes face to face with Nugent and gets bitten. Tiger, having fallen in love with Stella earlier, abandons his life as a house pet to live with her and the others in the woods. RJ apologizes for his actions. Verne tells him if he told them about his motives in the first place, they would have helped because that′s what family does for each other. Overcome with his emotions, RJ and Hammy share a warm hug. When they bring up the fact they haven′t foraged for food, Hammy reveals in his hyperactive state he filled the log they slept in with enough nuts to last them the entire year.
In a post-credits scene, the animals go to the vending machine seen in the beginning of the film, and make every snack to fall into the access bin. However, the big pile of snacks jams the access door from opening, prompting Hammy to remark that this is "kind of anti-climatic."