In the fictional town of Oakton City, a purple squirrel named Surly (Will Arnett) and his mute rat partner Buddy reside in Liberty Park where their thieving reputation has made them outcasts. A group of urban animals led by Raccoon (Liam Neeson) and his cardinal assistant are running low on food for winter. Red squirrel Andie (Katherine Heigl) and glory hogging gray squirrel Grayson (Brendan Fraser) compete with Surly and Buddy to scavenge from a peanut cart manned by Lucky (Scott Yaphe) and Fingers (James Rankin) who are casing a bank. The squirrels' efforts inadvertently end with the cart's propane tank exploding in the park after its cord was bitten by Fingers' pug Precious (Maya Rudolph). The runaway cart ends up destroying and burning the tree, where the animals store their food. Surly is banished and Buddy follows him..