After Cassandra's heart-wrenching betrayal, Rapunzel and her friends find themselves returning to Corona, but are surprised to find their beloved kingdom covered in shadows. An ancient evil is awakening. It started with the moonstone, but now Zhan Tiri has her eyes set on a more valuable prize. There is a young alchemist in the dungeons; he is broken, and his drained mind is weak, which will make him the perfect target for the evil warlock's return. How can a single drop of sun stop the entire world from transforming into darkness?