Cover image credit to Serenyan on Deviant art. Belle is visiting her grandparents during the holidays. One night she discovers a door in the old oak at the bottom of her grandmother's garden. Stepping through that door, she discovers a seemingly empty world in which grows some pretty strange plants. As she passes more and more time in "the tree world" she notices it change and become more and more vibrant. The shadow that has always lived there notices this too and begins to leave her clues so she can revive the dying world.