Mijn vader is een detective: De wet van 3

When detective Max is hired by fourteen-year-old Mara to find her missing mother, his son, Sam, and Sam's friend Ortwin start to worry. Max doesn't realize that Mara's a witch, and Sterre, the girl both boys fancy, is falling under her spell. As Sam and Ortwin do their best to expose Mara, they find themselves in a mysterious grove where strange rituals take place, things disappear, and no one is safe.