OKTOPUS is an abbreviation of "department for the control of deferred cases of department S". It was invented by the aging Captain Dítě mainly so that he could focus on the thirty-year-old Jordán case. He finds understanding in Lieutenant Colonel Schwarz, his superior, but when he assigns the young, ambitious Captain Fáberová to his hand, it soon becomes clear that he will not stick to just one case. The cases that OKTOPUS solves took place in the past, and it is up to the detectives to find new circumstances and clues that will help them finally solve the old cases. Their search will take us to the interesting surroundings of little-known Prague, among closed social groups, as well as to the players' dens and to the racetrack in Chuchli, where the bookmaker and bookie Dítě spends his free time.