East Berlin, 1975. When Oberleutnant Karin Müller is called to investigate a teenage girl's body at the foot of the Wall, she imagines she's seen it all before. But when she arrives she realises this is a death like no other. It seems the girl was trying to escape - but from the West. Müller is a member of the People's Police, but in East Germany her power only stretches so far. The Stasi want her to discover the identity of the girl, but assure her the case is otherwise closed - and strongly discourage her from asking questions. The evidence doesn't add up, and it soon becomes clear the crime scene has been staged. But this is not a regime that tolerates a curious mind, and Müller doesn't realise that the trail she's following will lead her dangerously close to home . . .

East Germany, 1975. Karin Müller, sidelined from the murder squad in Berlin, jumps at the chance to be sent south to Halle-Neustadt, where a pair of infant twins have gone missing. But Müller soon finds her problems have followed her. Halle-Neustadt is a new town - the pride of the communist state - and she and her team are forbidden by the Stasi from publicising the disappearances, lest they tarnish the town's flawless image. Meanwhile, in the eerily nameless streets and tower blocks, a child snatcher lurks, and the clock is ticking to rescue the twins alive . . .

The body of a teenage boy is found weighted down in a lake. Karin Müller, newly appointed Major of the People's Police, is called to investigate. But her power will only stretch so far, when every move she makes is under the watchful eye of the Stasi. Then, when the son of Müller's team member goes missing, it quickly becomes clear that there is a terrifying conspiracy at the heart of this case, one that could fast lead Müller and her young family into real danger. Can she navigate this complex political web and find the missing boy, before it's too late?

A secret State. A dark conspiracy. A terrible crime. Karin Müller of the German Democratic Republic's People's Police is called to a factory in the east of the country. A man has been murdered - bound and trapped as a fire burned nearby, slowly suffocating him. But who is he? Why was he targeted? Could his murderer simply be someone with a grudge against the factory's nationalisation, as Müller's Stasi colleagues insist? Why too is her deputy Werner Tilsner behaving so strangely? As more victims surface, it becomes clear that there is a cold-blooded killer out there taking their revenge.

1978 East Germany. Nothing is as it seems. The state's power is absolute, history is re-written, and the 'truth' is whatever the Stasi say it is. So when a woman's murder is officially labelled 'accidental death', Major Karin Müller of the People's Police is faced with a dilemma. To solve the crime, she must disregard the official version of events. But defying the Stasi means putting her own life - and the lives of her young family - in danger. As the worst winter in living memory holds Germany in its freeze, Müller must untangle a web of state secrets and make a choice: between truth and lies, justice and injustice, and, ultimately, life and death.

Dresden, East Germany, 1980 - A man's body is found buried in concrete at a building site in the new town district. When People's Police homicide captain Karin Müller arrives at the scene, she discovers that all of the body's identifiable features have been removed - including its fingertips. The deeper Müller digs, the more the Stasi begin to hamper her investigations. She soon realises that this crime is just one part of a clandestine battle between two secret services - the Stasi of East Germany and Britain's MI6 - to control the truth behind one of the deadliest events of World War II.