Plot and character go together like a horse and carriage. Okay, that isn’t the original Frank Sinatra song, but plot and character do combine to form something greater than their parts. The way plot and character interact is very important to storytelling, and if done badly, leads to terrible stories.
Plot and character
I should start with some ground work. When talking about ‘character’, I’m talking about character arcs, the way that the character changes in the course of the story. With ‘plot’ I mean the chain of cause-effects that move the story forward. Plot is the more difficult of the two to grasp, mostly because it’s not just ‘what happens’ in a story. Plot is the driving force of a story and the ‘what happens’ is just the result of that force and its interaction with the characters.
I’ve already written about how to structure your plot, and how to do character arcs. Where the two collide is where the story happens. I say ‘collide’ because character arcs are the result of external forces (the plot) pushing characters to change. People don’t change by themselves. If a person lives in the same place for twenty years, with the same people around them, doing the same job, there’s a good chance they won’t change a bit in those twenty years. They will change if they change jobs, or move, and they will change in a short time if something momentous happens to them, such as losing their partner. The plot is those events that push characters to change: a forced job-change, a plane crash that strands them on a deserted island, or a killer taking their spouse from them.
Types of plot
Depending on the character arc you’re going for, the push from the plot is different.
For a heroic-the-character-grows plot, the plot should slowly build up the pressure on the character, until it reaches a climax, where the character has no choice but to change or fail utterly (like the movie Constantine, for example).
For a hero-slides-into-evil-tragedy plot, the plot should throw up moral choices for the character, and have them continually choose the dark side as they slide into darkness (Falling Down).
And, in a story where the character has no arc, the plot should push against the character, but in a way that just shows off their abilities (Sherlock Holmes).
Mismatches
When this is done wrong, stories suffer, which can lead to some epic failures. I’ll use movies as examples, because I see more bad movies than read bad books.
A great example is X-Men: Days of Future Past. The protagonist of this movie is Wolverine, for marketing reasons. However, the characters with an arc are Xavier, Magneto, and Mystique. The plot pushes at them to change, not Wolverine. Wolverine just sits in the shadows with a cigar while the rest of the cast is running the story in the screen time left to them.
Pirates of the Caribbean 4 is the same. The plot revolves around Jack Sparrow, the slightly insane pirate captain, who goes looking for the fountain of youth. He does not change during the movie – whatever arcs could be done with the character were done in the first three movies. The plot is pushing at other characters instead, such as Philip and Angelica, who have arcs, but are not really the main character. Again, it feels as if Jack Sparrow is just… there.
When a story has a certain main character, and they don’t have an arc, the plot should not point a big neon arrow at other characters.
A different example. Recently, I saw the movie Jumper, which is groaningly bad. The main character is a young man who discovers he can ‘jump’ (teleport) to any place he wants at will. He uses his powers to rob banks and live a rich bad boy life. This seems to set up an arc for him to learn that using his powers for evil is wrong and he should redeem himself at the climax of the movie. Unfortunately, the bad guys are not after him for robbing banks. No, they just want to kill all jumpers, because they fear them. At the climactic ending, the protagonist overcomes the bad guy, and dedicates himself to destroying this evil organization. The plot pushes for a very different arc than the protagonist should have. It makes a complete a-hole out of him, because his thieving ways are never punished and seemingly vindicated by his victory.
Conclusion
Plot should match character. As a reader/moviegoer, this might help explain why you feel there is something wrong with certain movies. As a writer, if it feels as if you have to force the character arc into the story, or if you feel you are making up flimsy reasons for your character to make certain choices, then you probably have a mismatched character/plot.