The Peppercorns and the Curse of the Black King(2017)

Original title: Die Pfefferkörner und der Fluch des schwarzen Königs

Mia and her partner Benny, along with Mia's sister, Alicia, will be in charge of solving some puzzling cases that are happening in their city Hamburg. Surrounded by ghosts and mysterious characters this group of friends, accompanied by other young people, follow their clues.