In a land similar to New England, humans cut down the biggest beech tree and threaten the flying squirrels' nut supply. Duggan worries they'll starve. To find more, he crosses the busy highway and he almost gets flattened by a motorbike.
He meets new friends in the forest who help him out, when they're not fighting over a carrot or potato from their vegetable patch.
All Duggan wants to do is to get home. He builds devices to cross the highway but it's harder than he thought. The animals raid the commercial bakery, which churns out an endless feast of cakes and the flour, fat, sugar combo changes everything. Gopher twins Luca and Milo power up the metal pathway and Milo falls in the dough hopper.
Can Duggan get them out of there? Fatter from stuffing doughnuts, the animals don't move as fast as they used to!