Two serious criminals have been caught abroad. The German police pick them up and transport them to Cologne in a special compartment of the Nordexpress. The gang, led by their boss Sievers, plans to kidnap the two. Members of this gang replace the locomotive driver and train staff with their own people so that they can safely stop the Nordexpress at a location of their choosing.

Customs investigator Kressin, on his way back from Denmark, where he was dealing with porn smuggling, is on the train. He manages to prevent the kidnapping of the serious criminals.

Jochen Bähr, department head in a pharmaceutical company, is found shot dead in his boat early on a Sunday morning. At the crime scene is his young son Thomas, who is in shock and unable to speak. Schimanski, who needs the boy's statement, tries to break his encapsulation. He has initial success - then Thomas is kidnapped under the eyes of the inspector.