The Lahti File tells the story of Ian Munro, a British agent sent to the Finnish town of Lahti to investigate strange and dangerous events. People are dying, fish are disappearing, and something is clearly wrong in the area.
During his investigation, Munro discovers that powerful people are hiding a serious secret. When someone he meets is killed, he realizes the situation is very dangerous and that he is also being watched.
As he goes deeper into the mystery, he faces threats, chases, and attempts on his life. In the end, he uncovers the truth behind the strange events, but not without risk and danger.