Johan works in tandem with the GSI organized crime unit to bring in a cadre of armored car robbers

After causing a commotion with his last assignment, Falk has been given a desk job, which hardly agrees with his personality, and he ends up accepting an offer from an old friend to buy into a private investigation agency. Another friend of Falk's, Sven, purchased a business in Estonia, and when local gangsters attempted to pressure him into paying protection money, Sven retained the services of Nikolaus Lehmann, a burly private eye, to throw them off his trail. However, Lehmann does his job all too well, murdering the racketeers, and then threatening Sven and his family. With no where else to turn, Sven asks Falk to help him deal with the crazed Lehmann; Falk agrees, but soon realizes he's dealing with a more dangerous man than he imagined when Lehmann kidnaps Falk's wife Jeanette, and then releases her with a time bomb locked around her neck, demanding that Falk hand over ownership of his detective agency to Lehmann.