While interrogating König, Rath loses control of the situation. Charlotte moonlights to make ends meet. An alter ego commits a betrayal.

Greta goes on a romantic outing with Fritz. Krajewski finally reveals where the film is hidden. A new patient is brought to Dr. Schmidt for treatment.

Rath's pharmacist gets shady instructions. Rath learns who's behind the train smuggling operation and why, and recalls the last time he saw his brother.

At the May Day protest, police action spirals out of control. A body is found in a canal. An unsuspecting Svetlana returns to her apartment.

Kardakow realizes his first instinct was correct. A photo enlargement yields two leads. Rath and Charlotte get key intel from a colorful character.

Rath confesses to a priest -- and later to Wolter. Charlotte charms medical student Rudi into performing a secret autopsy, which uncovers a vital clue.

The freight train arrives in Berlin. Tempers explode in Charlotte's household. Aspiring inspector Jänicke makes use of a surprising skill.

In 1929, a freight train traveling from the Soviet Union is hijacked. Meanwhile, Chief Inspector Gereon Rath from Cologne pursues a mission in Berlin.