As a young and recent graduate, police assistant Signe Brask is put on the case of a 10-year-old girl who disappeared without a trace during a Christmas trip with the family. Despite massive search actions, the girl was never found. The family is torn up by the tragedy, and Signe Brask remains the only one who follows up on the case on behalf of the police force. Ten years later, a girl shows up on Copenhagen's train station, claiming she is the missing Mille. Where has she been in those ten years? And is she who she says she is?