In the middle of the day, on a golf course near Frankfurt, Frederick Seibold (Helgi Schmid) is struck down by four men wearing dog heads. When he regains consciousness in a dark basement, the two Frankfurt chief inspectors Anna Janneke (Margarita Broich) and Paul Brix (Wolfram Koch) are already entrusted with his case: Frederick's ex-girlfriend, Bille Kerbel (Britta Hammelstein), had a severed finger received, which she took straight to the police. Konrad Seibold (Bernhard Schütz), Frederick's father, a well-off commercial lawyer, does not see the point in paying the ransom, as he believes his son Frederick himself was behind the kidnapping. Janneke and Brix are surprised by Seibold's stubbornness, who also received a finger and didn't react.
However, when it turns out that the severed fingers did not come from Frederick, the father seems to be right. Via Bille, the inspectors' trail leads to Conny Kaiserling (Christina Große), who runs a studio for women's self-defence courses. Brix comes up with the idea of smuggling Fanny (Zazie de Paris) there undercover. Janneke and Brix are called to the Taunus to a woman's corpse that has been placed there. Antonia Wagner, the dead woman, was apparently pierced by a fence post. In search of outside influence, the forensic pathologist finds fragments of Frederick Seibold's skin under her fingernails. Was Antonia involved in the kidnapping?