Based on Kristina Ohlsson's novels, the series follows unconventional but cunning criminologist Fredrika Bergman who joins a special investigations unit in Stockholm.

Criminologist Fredrika Bergman suffered a tragic car accident and has been working as an investigator for the Stockholm police ever since. The opening episode deals with the disappearance of a five-year-old girl at the central station. Fredrika and her experienced colleagues Alex and Peder start investigating. One lead takes them to the father of the five-year-old, who lives separately from his family. When the police discover child pornography on his laptop, the girl's abductor seems to have been found. But then another girl disappears... In the further episodes of the series, Sweden's capital is repeatedly shaken by brutal violence.