Hunkeler, now a retired inspector of the Basel police force, is hospitalized following an operation. He's sharing a room with cancer patient Stephan Fankhauser, an old acquaintance and former head of Basel Volksbank. One night, a groggy Hunkeler witnesses something that makes him question his senses: a young nurse is administering an injection to his friend.

When he is told the next day that Fankhauser has died, Hunkeler grows suspicious. The body is quickly cremated with no autopsy performed, leaving Hunkeler determined to get to the bottom of the matter. His unorthodox investigation uncovers truths that will threaten Switzerland's carefully curated reputation of neutrality during WWII