Recently, I'd noticed that murder mystery settings are often unvaried, usually taking place in a setting grounded in every-day reality. When I pointed this out to a group of friends, outwardly expressing my confusion as to why most murder mystery stories don't take place in settings grounded in fictional worlds and as apart of an overarching narrative while simultaneously internally brainstorming ideas to run with the idea of presenting a murder mystery in an unconventional environment. One of them responded that the reason these types of stories are often placed in familiar environments is because it helps detract from the mystery by allowing a good percent of the focus on exposition and description being directed at the mystery almost exclusively and that by having to present information building an unfamiliar environment would detract from the mystery in the hands of an unprepared writer. To use as an example, I'll present a quick overview of a concept I had while discussing this with friends (with minimal development or expansion upon the idea): A conspiracy group takes in a hostage for questioning, and someone trying to compromise the group's endeavors murdered the hostage. The mystery is placed in the hands of one of the members of this organization, who has to find out who is trying to dissolve the conspiracy from the inside in coordination with his usual work haul. Now, chances are I definitely will not run with this concept, but its merely the most extreme example I could provide so any explanations for how to deal with it and any answers to my questions I could apply to a less extreme usage of this idea of unfamiliar settings on a smaller scale. 1: How would one fluently provide information on the investigation of the murder as well as providing information on this new setting where the conspirators exist and the job they do without detracting from any of them? 2: Given that the story would likely have a large scale due to needing to explore the new environment, the mystery would need a scale to match. What else could the enemy of the conspirators do to further his endeavors to dissolve the organization, relating to his initial action, to subsequently leave clues for the MC to follow? 3: How would the MC's normal work and the new mystery correlate? 4: How could the murder mystery and the overarching narrative fuel one another? How could they correlate? How would one drive the other? How would they feel like they belong together in the same narrative? And any other general tips for running with unconventional settings in a murder mystery on an equal or smaller scale would be appreciated.
It's hard to answer this without understanding what the conspiracy group is striving to do, but I'll try. 1: Balance is a vital part of pacing, you would need to establish the goals of the group but not overload the mystery with it. Basically, there should be just enough of the conspiracy so the reader understands why it is relevant to the plot, but I personally wouldn't put in more. 2 and 3: You'd need to establish the characters to answer these. Once you have that, they would most likely be able to tell you themselves. Agatha Christie is said to have worked her stories backwards and establish the end before the beginning. 4: The conspiracy group and its goals are involved in the murderer's motive. Maybe the balance between logical investigation and paranoia about their plan being known would come into play here?
I'm not going to specifically answer your questions right now because I honestly feel like S A Lee did a good job of answering them already. I'd instead like to just throw around a few ideas that may or may not ultimately be helpful, but that I think are worth considering. I've noticed in some books I've read that there are indices to help the reader understand the world they are reading about. If you were to use something like this, you could have a glossary, maps, charts, or whatever other pertinent information in its own section where it wouldn't detract from the narrative itself. You could include it at the end of the book, or at the beginning, and anytime you made reference to a new concept that needed explaining, you could include a symbol of some sort indicating that referencing the indices would be a good idea. Alternatively, you could include annotations, not unlike the ones included in literary textbooks, for a bit of exposition when needed. This way you're including the necessary world-building material and giving your readers access to it without taking time out of the actual telling of the story itself. Another method you could employ would be to provide relevant information, in small enough doses so as to remain subtle, in regular character interaction. For example, you could explain things through casual dialogue, or through a legend or folktale the characters in your world would be familiar with that bears some relevance to the plot. Including pertinent world-building information in this way feels more natural when executed properly and makes the lore seem more accessible, rather than simply shoved on all at once. It's more manageable for readers if they can pick things up during the course of events than by having to pause to learn a new concept, and also helps the writing to flow better. Most readers would rather the information come to them naturally than to be bogged down with paragraphs of exposition that will end up making them have to backtrack if they want to follow the plot, so this method keeps them engaged in the work while teaching them what they need to know about your particular fictional world. As a final note, I'd like to say that I find the idea of writing a murder mystery in a non-mundane setting to be extremely refreshing and intriguing. It's something I find rather bizarre as well, to tell the truth. Perhaps people don't do it simply because they're unsure how to present the mystery in the midst of all of the necessary new information? Regardless, I wish you luck in your endeavor.
So I'm also not going to answer the question directly, but I think part of your question rests on the assumption that most murder mysteries do in fact take place in familiar settings (at least familiar to author - I like to read Scandinavian crime novels precisely because the setting is unfamiliar to me, but the authors know those places.) Anyhow, I think that assumption is a little flawed. Or, more specifically, it's only true if you apply it to murder mysteries that are marketed in the Mystery or Crime genres - those genres have a lot of aesthetic components, and in the Crime Novel space, gritty realism is the actual selling point not a side effect. A lot of mystery-ish plots with non-police protagonists do exist - but mostly these end up in the Thriller space rather than the Mystery Space or the Crime Novel space. In those you tend to have someone whose occupation suddenly gives them a window into a case, and if they're working outside the law, they usually end up getting chased by both the baddies and the law in the process...the chase being the central element of a Thriller. (For a good example of this, see Peter Hoeg's Smilla's Sense of Snow - in that case the protag is an unemployed academic expert on ice crystals who realizes that the police are involved in a conspiracy to cover up the murder of a child in her apartment building, because she can figure out that the police story on the child's death doesn't match the patterns in the snow.) Mysteries with non-traditional and non-realist settings also exist - there's an entire subgenre of Sci-Fi and Fantasy detective stories - but those are going to get shelved with Sci-Fi/Fantasy, not in mystery. Some good examples would be Michael Chabon's The Yiddish Policemen's Union (a pulp detective story in a world where Jews were settled in Alaska post-WWII), Lavie Tidhar's Osama (a pulp in a world where terrorism doesn't exist and Osama bin Laden is the fictional hero in a series of novels), Cassandra Rose Clarke's Our Lady of the Ice (A crime novel set in a domed city in alternate-1960s Antarctica), and Mur Lafferty's Six Wakes (a space opera murder mystery where six clones wake up and realize that the reason they've been activated is that the people they were cloned from are all dead).
Hey, my work is literally this, a murder mystery set in a fantasy world of my own creation, so I should probably have answers for these questions, and I do! Bear in mind, my answers are for the context of my own setting and story. 1: How would one fluently provide information on the investigation of the murder as well as providing information on this new setting where the conspirators exist and the job they do without detracting from any of them? Link them. Make the mystery link to important parts of the world you created. Mine ties back to a magical catastrophe, history of the local noble family, and a current desire for the local nobility to create a cultural resurgence. 2: Given that the story would likely have a large scale due to needing to explore the new environment, the mystery would need a scale to match. What else could the enemy of the conspirators do to further his endeavours to dissolve the organisation, relating to his initial action, to subsequently leave clues for the MC to follow? I went in the other direction. They mystery involves shattering a preconceived notion of the world, however, my environment is a single city. This allows me to focus on showing the one area of my world, while referencing outside points that will be developed in later books. 3: How would the MC's normal work and the new mystery correlate? He was already something of a problem solver, meant to keep his faction on good terms with nobles, so this is just an extension of that. 4: How could the murder mystery and the overarching narrative fuel one another? How could they correlate? How would one drive the other? How would they feel like they belong together in the same narrative? It depends. I don't have an overarching narrative planned at the moment. The important thing to realise is that books can take place within the same universe, but not have an overarching plot or even the same characters.
