Oak is a mythical little leaf girl who lives with her leaf parents on the branch of an ancient oak tree. She loves nothing more than exploring and playing with the creatures and insects of her tree world. But as the weather shifts and the slow season begins, Oak realizes that she and her family must leave the tree. It is time for them to float down to the ground where they can nestle into their winter acorn home, and see out the cold until spring returns once more. But Oak refuses to move - she doesn't understand why they have to go and she's afraid of what's next. Why does change feel so hard?