Rainer Maria Schlaicher's worst nightmare comes true: His father has announced his visit, and just now everything is going wrong. While the test thief has to have an extremely valuable painting restored and meets a woman he should probably stay away from, he stumbles upon a corpse in the middle of a marketplace at night. Commissioner Schlageter is at a loss and increasingly focuses his investigations on Schlaicher, who is reluctantly trying to find the murderer on his own. The connection between the Baden Revolution, Kommune 1, or swastikas and the death of the pharmaceutical entrepreneur can only be uncovered with the help of his pubescent son, the sales-driven neighbor Trefzer, and his Basset hound Dr. Watson.