In 1978 East Germany, nothing is at it seems. The state's power is absolute, history is rewritten 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.