An ex-terrorist, Madina Taburova, who was presumed dead, turns up in Helsinki seeking political asylum. Using a fake identity, the Intelligence Agency officer Mari Saari has to befriend this ex-terrorist to find out why she’s here. In order to uncover the mystery, Mari Saari has to form an unlikely partnership with an older streetwise narcotics cop. But everything is not as it seems.

During the 1950s, Helsinki was the focal point of the Cold War, as global powers and their intelligence agencies coalesced in the small neutral country that stood between the East and the West. Shadow Lines is an international spy thriller that follows a secret intelligence team whose mission is to defend the independence of Finland no matter the cost.

Lauri Räihä, a criminal investigator from Helsinki, is sent to investigate two murders that have occurred in the northern Finnish town where he grew up. The assignment offers Lauri a way out of confronting his own problems.