Overview: A missing child is at the center of Inspector Helen Dorn's investigations. Mia, the four-year-old daughter of the wealthy businessman Hans Thomsen, has disappeared under mysterious circumstances. The family members are under shock; a kidnapping seems likely. While Mia's mother Inga tries to keep the family together and prevent an escalation, her husband wants to find his daughter on his own. But why does he head so assuredly for Rotterdam? After a difficult start at police HQ with her new partner Gregor Georgi, Helen Dorn begins to discover some very surprising things about Gregor. He, meanwhile, sets out to understand Helen better by uncovering her past…