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.
Kekkonen takes office and the Nyrkki buries one of its members. Helena is still searching for answers about her past. A routine gig turns into a war zone when a new enemy appears on the scene.
Helena discovers a shocking secret about her mother. Helena and Olavi are tasked with finding out who is behind the general strike while Aune and Yrjö search for their enemy.
The strike ends and Kekkonen rewards Yrjö by sending him on leave. Helena and Olavi have a fun evening together while Tabe meets a new acquaintance. Aune visits an old friend.
Nyrkki finds out that the government is about to attend a top secret meeting, and fears for the worst. Helena and Olavi resort to old tricks and Tabe saves the day.
Nyrkki is on the verge of falling apart and is questioning who it can trust. Helena takes a huge risk to save Finland and find the truth about her mother. Olavi pays a high price for his loyalty.
While Helena fights with her past and Yrjö for his life, Olavi makes a hard decicion. Aune enjoys the power she has gained and Tabe decides to turn over a new page in her life.
Helena meets her father and Tabe meets an old friend. Helena makes a deal with the devil. Olavi is on his way to hell. Nyrkki must save Finland, but is it too late?
As they fight for their country, the members of the Nyrkki learn that they must join forces once more to save themselves.
