A brutal murder shakes the Westphalian small town of Unna during the annual old town fair. A dentist is found strangled in the city park. Around her neck hangs a gingerbread heart with the inscription "A final greeting, G." Commissioner Maike Graf and her colleague Max Teubner begin their investigation and soon come across a hot lead when another murder occurs. Once again, the victim is wearing a gingerbread heart, and it seems only a matter of time before the murderer strikes again...