It is a wonderfully stormy night in Hasselbach Valley. Laughing, Schimmerie Harztropf and her best friend Luminus chase the autumn winds. But suddenly, the little forest fairy loses control, gets caught in the branches of the old willow tree—and disappears without a trace.
While the fairy wolf Luminus does everything he can to save his girlfriend, Schimmerie finds herself in a strange world. Deep underground, she ends up in the clutches of a joyless people, the Faseltaki. The cruel King Frotsch and his henchman Löwengram prevent her from returning home.
Fortunately, the friendly forest mouse Pippa takes the forest fairy under her wing. Mikka, who is different from the other Faseltaki, also tries to protect Schimmerie. Because Mikka has a secret.
Can the friends break the spell of the Sinister World?