The Secrets of Grandelva is a mystery-adventure series about a young orphan mushroom named Rune and her group of friends who uncover secrets about their rainforest home -- where their community unknowingly relies on celestial beasts: secret mythical creatures that sustain life in the rainforest by the use of a magical root system. Preoccupied with avoiding predatory slugs and intra-community struggles, the mushroom village fails to see the reality of their world deteriorating around them when  their source of nourishment is captured by a mysterious foe. Their only hope is Rune and her young band of mushroom friends who embark on a quest to discover the truth of the past and learn how their roots can heal the rainforest.