Freedom: seven letters that can start an avalanche of impassioned speeches and any number of revolutions. Also, something that characters and players are frequently deprived of in fiction. A frequent plot element used in stories is to trap the characters in an inescapable location. Well, mostly inescapable. The only means of escape is a damaged car, plane, ship, space ship, Time Machine or weirder vehicle. In order to escape this Closed Circle they have to repair the vehicle, which won't be easy (otherwise, what would they do for the rest of the episode?). Usually this will require a chain of Fetch Quests for tools, parts, fuel, and potentially crewmembers.