- A villain comes up with an evil plan.
- The villain begins to put that plan into effect.
- Our hero sees the effect of that plan.
- The hero figures out who the villain is and stops him/her.
In order to get around this problem, most mysteries add step 1a: Life complicates the villain’s plan before the hero finds out about it.
Usually this means that something has gone wrong with the villain’s plan: Someone else already found out about it and had to be killed, for instance. Or another conspirator had to be knocked off. Or an innocent bystander was killed by accident as part of enacting the plan.
This makes the mystery more satisfying, because it makes the quo bono much harder to figure out. The initial crime the hero discovers is not something that obviously benefits the villain. The villain has killed someone they didn’t originally intend to kill, merely in furtherance of the conspiracy, rather than in pursuit of the original benefit.
Zootopia is another mystery in which things haven’t gone according to the villain’s original plan, in a way that complicates the story, and makes the mystery much harder to solve. (The difference here is that the complication winds up helping out the villain.)
Here’s the original plan: Assistant Mayor Bellwether (in collusion with some chemists and a sniper) has been shooting predators and making them go savage, in order to make all predators look bad, especially her boss, Mayor Lionheart. And indeed, this movie could have begun with predators going savage in public places. Some would blame it on their DNA, but our heroes would investigate, find the poison, track it down to its lab, etc. It would have been hard to stretch that story out to 108 minutes.
But the case isn’t so simple, because reality has interfered with Bellwether’s plan: Mayor Lionheart has found out about that 14 predators have gone savage, but he’s decided to hush it up: He’s had them rounded up and taken to a defunct hospital for testing, so as to avoid a panic.
(In this instance, the complication will slow things up for her, but will ultimately benefit her more than she could have dared hope for. This is perfect: All she has to do is point our heroes to the mayor’s facility, and he’ll actually be arrested, rather than merely forced out, and she’ll become mayor instantly. Originally, she had wanted the poisonings to gradually create a panic, but this works even better: Now all fourteen cases that the mayor has covered up will come out at once, and the panic will be instantaneous. Nevertheless, things have not gone according to plan.)
The good news for the movie is that this complication obscures the villain’s plot, so it’s not obvious to us. Our heroes spend most of the movie investigating Lionheart’s conspiracy, not Bellwethers. Our question is: Who has kidnapped these predators? The fact that they’re going savage doesn’t even come up until the movie is half over. Our eye is kept off the ball by the complication.
We’re always several stops behind the main plot, so we never get to slow down and ask the obvious question: Who benefits? If we had, the answer would have been obvious. As it is, neither we nor the heroes ever get around to asking that question until the answer is literally staring us and them in the face.