Editorial: Four Tips For Writing Mysteries.
So, I've been reading The Maze Runner lately. It's good, I'm enjoying it. But I also know that in future books, it's going to become an absolute trainwreck, and a large amount of that is due to poor handling of its central mystery.
So I thought I'd provide some tips. I did have a different editorial planned for today, but after - confusing and enraging events of the morning, this one seems a little easier on the soul.
1. A mystery must be planned in advance.
This one is more logistical than anything.
Mysteries are holistic in nature: In a mystery, all things could (and arguably should) contribute to the mystery or the solving thereof in some fashion - certainly your audience will be picking apart every little thing.
For that reason, a mystery is one form of story that needs to be carefully planned. You need to know where it starts and where it ends, and you need to know what the answer to the mystery is, even if you never intend to tell your audience. You need to know where you're going to put clues, what those clues are going to be, and where you're going to misdirect your audience.
Essentially, before you start writing, you need to plan meticulously.
2. The answer must be as interesting as the mystery itself.
Mysteries are fun and intriguing, and getting the answer to it will kill your mystery and all the intrigue associated with it dead. So your answer has to be just as fun, although not necessarily in the same way.
Broadchurch is a fine example of it, as the answer to the mystery brought with it a high emotional impact, both for the characters and the audience, and tied into the series' themes of a town being torn apart by its secrets. The answer isn't necessarily intriguing in the same way the mystery was, but it brought other boons with it, which is part of why it was so well-received.
The sequels of The Maze Runner, on the other hand, are an absolutely terrible example of this. The answer given to the mystery there is incoherent, ridiculous, cookie-cutter, and ultimately unsatisfying, failing to live up to the expectations set for it by the first installment.
3. The audience must have the information to figure out the answer you'll give before you give it.
If you're writing a murder mystery, you're playing a game with your readers. You are setting before them a challenge - to figure out the mystery before your sleuth does. It's hardly a fair challenge if they don't have all the information they need to do so.
Furthermore, you need to give them at least the minimum of information by which they would guess the right answer as early as possible. No introducing your culprit halfway through the story, or in the last act: They need to be introduced as quickly as possible. This is why so many mysteries introduce suspects in groups: While it can be a little overwhelming for the reader or watcher, it means you can introduce your culprit while hiding them amongst four or five other potential culprits.
You can use misdirection, if you like, but there must always be a solid core of evidence from which a reader can come to a decision as to who they think it might be. Oddly, given that it's kind of incoherent at points, the visual novels Umineko no Naku Koro Ni do this exceptionally well: Much of the gameplay is built on two principles: Any statement given in red is the truth, and any statement given in blue is the truth also, unless contradicted by a statement given in red. It's a gameplay feature that allows an audience to draw conclusions from information given to them, while also allowing a degree of mystery and interpretation (since many statements can be interpreted in multiple ways, or phrased deceptively while still being true).
4. ... But you don't have to give an answer at all.
In a certain kind of story, you can leave your mystery unanswered. In a certain kind of story, leaving your mystery unanswered works a lot better, even when your mystery is a central part of the story. Cube, a 1997 Canadian psychological horror film, is a prime example of this: The five main characters are trapped in a vast cube composed of many smaller cubes, each one containing death traps. At no point is the purpose of the Cube ever established, and it appears to have no oversight: Characters speculate on it, with one character positing that there is no purpose behind it, or that whatever purpose it had has been long since forgotten. The most clue we get to any of it is that one of the characters within designed the outer shell: He doesn't know who for or why, and he wasn't aware of its purpose.
The books Incarceron and Sapphique are similar: The nature of the eponymous Incarceron and the mythical prisoner who escaped, Sapphique, are entirely unclear: It's made unclear if Sapphique is any of several surviving characters, or if he's long dead. In fact, it's not even made clear if Sapphique is or ever was a real person, or if it might be the name of some kind of control system for the prison, or if it might be a role that different people are meant to fill. Accounts differ, and all of the information received to support any viewpoint is unreliable.
What connects these two stories is that they both have conflict other than solving the mystery: In a detective novel, the central struggle is 'I have to solve this mystery and catch the responsible person.' In both Cube and the Incarceron books, the struggle is 'We have to escape this vast, mysterious structure.' The characters are within the mystery, and seeking to exit it. This is key: You can have a story where the central mystery isn't answered - but you cannot have a story in which the main plot isn't satisfactorily resolved by the end, and if solving the mystery is your main plot, you have to give an answer.
The other common theme between these two is that no answer would be satisfying. Both draw off the mystique off mystery, and to reduce that down to a clear answer would spoil it. It is, in a way, more satisfying to let people sift through the evidence available and come up with their own interpretation.
(Incidentally, this is the direction I thought - and hoped - The Maze Runner would go, but instead the two books afterwards had it devolve into an incoherent mess in an attempt to give it an answer. What can you do.)