After a succession of suspicious deaths at Helsinki subway stations leaves police baffled, Detective Sergent Timo Harjunpaa of the Helsinki Violent Crimes Unit takes up the case only to uncover overwhelming forces of evil. With no witnesses to the deaths and closed-circuit tapes revealing even less, Detective Harjunpaa slowly discovers the madman behind the murders-a fanatical priest who brainwashes teenagers into carrying bomb-filled backpacks. No stranger to the seamier side of human nature, Detective Sergent Harjunpaa must now face the most terrifying case of his career.