Subplots are, at best, distractions.
That’s a good thing. When your main plot is moving slowly, or has to wait for something to happen, a subplot can come in and keep people interested. Or, when something awful is happening and you don’t want the reader to put down the book because it’s too intense, a subplot can be just the thing to gloss it over and help bring the reader through. In short, subplots are great when you need to distract.
But subplots can’t just spring from nowhere. If you only acknowledge the existence of subplots for the few moments when you need to distract from the main plot, it’s going to feel contrived. The subplots must be there already, available to be used for your purposes… but they’re still distracting. Subplots aren’t as important as the main plot— that’s why they’re called subplots.
Does that mean you’re allowed to ignore all subplots and only go with one plot line for the entire story? No. It’s said that characters interact in pairs— there’s a different relationship between each set of characters in your cast. That’s a subplot for each pair, really. Not only that, but we’ve seen before that subplots can cloud a mystery or prolong a romance. Subplots have many uses, from pacing to developing character. They’re useful, naturally. But they’re still distracting.
At this point, it seems like subplots are more trouble than they’re worth— putting them in means distraction, leaving them out means less to work with in terms of plot. There’s no way to win… is there?
Of course there is. Think about it. Distractions are all alike; red herrings, jokes, and promises are all distractions. Even important things can seem like distractions. There’s an easy way to deal with those distractions, no matter what size, and it works on subplots just as well.
Make them necessary.
Easy— but not so easy. It’s a big job, of course.
The first step is to make it pay off. Whatever the subplot is, make sure it has a resolution that links to the main plot. If it’s an ongoing argument between two characters, make sure those two characters make up and work together to resolve the main plot. If it’s a trail of red herrings, clouding the waters of a mystery, make sure that smaller mystery is solved first, so the water is clear enough to see the truth. When you complete this first step, it almost doesn’t matter if you finish the job of making this subplot necessary; when you make sure the subplot pays off its own promises, it pays for its distraction.
That first step is enough to make you not fail. It’s not enough to make you an expert, but it’s enough to keep you afloat.
Please don’t stop there. Too many writers, including me, have stopped there because they don’t have the time, or they don’t know enough, to make it any better. Don’t stop there. Just treating subplots this much differently will bring you from mediocre to amazing.
So, what else is there to do? The second step is a little harder than making the subplot pay off; making it necessary earlier in the story.
This can be done in several different ways, depending on the subplot. Whatever the subplot adds to the story, make sure it adds it throughout the story as well as at the end. If the subplot adds humor, make sure it’s adding humor where humor is desperately needed, and never where it’s useless. If it adds conflict between characters, make sure that conflict never disappears without explanation. Whatever it adds, make sure it adds it.
This will require a little bit of thought, but it will accentuate the main plot more than it distracts. Combined with the payoff that comes at the end, it will feel almost completely necessary… but not completely.
The last thing to do is a micro-edit thing: make it smooth. Don’t make it obvious how much the subplot is necessary. Don’t make it obvious when your gears shift from main plot to subplot. Don’t make it obvious how much you’re tiptoeing around to keep from being distracting, because that’s more distracting than any subplot you can think up. Instead, bury the subplot. Even though you’ve worked on it, even though it’s necessary, even though you want the world to know it’s not distracting, bury it. Make conversations and thoughts flow from one topic to another. It’s going to be difficult, but that’s exactly why mediocre writers leave their subplots at the first step.
It gratifies the audience to realize that something they noticed at the beginning of the story has a part to play at the end. But it gratifies a reader more to realize that something they didn’t notice at the beginning has a part to play at the end. That’s where the best surprises come from, and where the best writers show their worth. Anyone can make a distracting thing pay itself off, but it takes skill to pull a payoff from nothing.