Zwei Seiten des Abgrunds

During an operation, policewoman Luise Berg surprisingly meets the murderer of her daughter Merle, who was killed years ago. He has ended his prison sentence early and Luise suspects that the supposedly reformed Dennis is pursuing a revenge plan. Neither her ex-husband nor police chief Tesche take her concerns seriously. When a gruesome murder occurs in Belgium and Dennis moves dangerously close to her family, Luise has to face her painful past.

During a SEK mission, Luise exceeds her competencies and meets with a lack of understanding from her new team partner Nadisa. Luise suspects connections between Dennis and the murder in Belgium, investigates on her own and finds a USB stick. During a raid on a techno club, she meets her underage daughter Josi and has no idea how menacingly Dennis has already worked his way up to her family.

The USB stick secured by Luise reveals something shocking: children have been abused on the campsite for years. Was Dennis one of the victims? When another murder occurs, Luise has no more doubts: Dennis keeps killing. He appears unimpressed by Luise's private investigations. Meanwhile, a world collapses for Josi when she realizes that her new boyfriend Luca is not who he claims to be...

Luise establishes a connection between the murdered Schwebebahn driver Marcel Stuber and Dennis. She suspects further sexual assaults. Because of her investigative solo efforts, she is suspended from duty. Meanwhile, Josi entangles herself in a web of lies to cover up her involuntary connection to Dennis. When she meets him again at a party, things escalate and Dennis puts Josi in mortal danger...

Luise can hardly believe it: Dennis is actually arrested. Merle's death seems to have been atoned for and Josi thinks she's safe. But due to a lack of evidence, Dennis is released, he lies in wait for Josi and blackmails her with a sex video. Josi realizes that no one will understand that she - albeit unknowingly - got involved with her sister's murderer. She then flees to Belgium with Dennis.

The second cross at the Merles memorial by the river turns out to be another bait that Dennis set out for his final confrontation with Luise. He barricaded himself in a remote hut in the Belgian High Fens and is now holding Josi hostage after a failed attempt to escape. Luise follows them both and reaches the hut, but is overpowered by Dennis. Then Nadisa appears on the scene, having secretly followed her colleague Luise...