Julia is a trainee police officer living in Cologne. In Lydia she has found a friend and advisor, while her academy trainer, the paternal but tough Chief Inspector Roosen, always has his eye on her. Julia is the baby of the group, unbiased and curious. In addition to her demanding classes, she is always on call for her paraplegic father, Wolfgang. Her mother died shortly after she was born. When..

After Julia sees the swastika tattoo on Nick’s back, she runs a background check on him on the police computer system. Shocked, she discovers that he is using a false name and is registered as a serious criminal offender and right-wing extremist. Julia goes to the police academy intending to steal a weapon so that she can confront Nick. But she is caught by her trainer and so tells him every..

After the attack, Julia wakes up in the hospital; Nick has disappeared without a trace. When she tells her father about a particular ring that the unknown attacker was wearing, he is shocked. He believes that this is a "Westwall ring", a neo-Nazi emblem and warns Julia that she is in great danger. Julia refuses to go into hiding; she wants to find Nick. Meanwhile, he wakes up in a guest..

Julia’s life is a dark puzzle. She starts to investigate her own past and finds a connection to Ira and an old sawmill on the Westwall. But the jigsaw pieces don't fit together. Meanwhile, an incensed Inspector Roosen confronts Henning, and it transpires that the far-right puppet master Henning is actually Badtke, a high-ranking official from the State Office for the Protection of the Co..

Julia wants to confront Ira. She travels to the Westwall and starts looking for the sawmill. Nick follows Julia, so that he can finally tell her the truth. While Keppler discovers more and more clues that the group are planning a horrendous bombing campaign, Roosen talks to Henning/Badtke. He accuses him of being responsible for the death of Julia's father. The intelligence officer believes th..

Nick too has arrived at Ira’s hideout on the old Westwall, and he manages to grab Ira. But Karl rushes to her aid and knocks Nick out. Together they bring Nick to the cellar of the sawmill and torture him for information. In the meantime, Keppler is trying to find the mole in the Office for the Protection of the Constitution. When the LKA accesses the data on Roosen’s burned cell phone..