What do you do with subplots?

If subplots are “a secondary sequence of action,” what’s the point of having them? Isn’t the primary sequence of action enough?

There are quite a lot of points, it turns out, depending on the sort of story one is writing and where one wants it to go. A judicious choice of subplots can broaden the scope of the story, or deepen the theme. Subplots can contrast with the main plotline or intensify it; they let the author examine an argument from multiple angles in the same story, or examine multiple arguments; they allow development of secondary characters and revelations about major characters that don’t fit in the central storyline. And regardless of what else they do, subplots by their very nature add richness and complexity to almost every aspect of the story.

It is, however, rare for an author to be able to pull off all of the above at the same time. It usually takes more than one subplot, for starters, and it becomes fatally easy to multiply the number of subplots beyond the author’s ability to keep track of and/or keep coherent. Some years back I read a novel that had so many subplots that it took the author three or more chapters just to check in on current developments. Periodically, I ran across a scene with a new viewpoint character, who turned out to belong to a subplot that hadn’t been touched on for a hundred pages (it was a very fat book). It was disconcerting, and eventually put me off the book entirely.

Back to what subplots are good for. Possibly the most common use is in character development. The protagonist’s long-buried anguish over the death of her brother when they were twelve may have nothing to do with the thriller plot about stealing the secret plans from the foreign spies, but it makes a dandy subplot. The space opera hero’s only chance of showing his artistic side may be in the comic subplot about decorating his mother’s apartment. The sidekick may never get a chance to be heroic or tender or intelligent in the main plotline, but can be all that and more in the subplots. Motivation, especially when it is complex and involves backstory or character growth, is often explained in a subplot.

Subplots often reflect different sides of the central theme, problem, or argument. Sometimes, this is fairly direct, as when you have three or four groups of characters all chasing after exactly the same McGuffin, but in different ways for different reasons. The main character’s group is presumably the one we’re expected to agree with and/or sympathize with the most, but the author may want to show that other people have different views about when and how to achieve whatever they’re all after, and/or equally valid but different ideas of what to do with it afterwards. This type of subplot structure can be very difficult to distinguish from a plot arc or a braided plot.

Other times, the subplots parallel and illuminate the central plot, rather than being directly connected to the same central problem. A Romance novel in which the main character has to choose between two suitors, one socially acceptable and one not, might have subplots in which a different character is desperate for such a choice, another character makes a different decision than the one the protagonist eventually chooses, and several friends or relatives of the protagonist who made similar choices at some earlier point have to deal with the negative consequences of their decisions (e.g. reconciling with family who disagreed with that choice, living with or escaping an unhappy relationship, beginning or refusing a clandestine affair with the rejected suitor, etc.). This kind of subplot can be very effective if two of the characters have made different decisions, both of which are right (or wrong) for the particular character.

Subplots can also be indirectly related to the main problem. A main plotline that involves a protagonist who discovers a close friend’s criminal activity and who must then decide whether or not to report it may have subplots in which other characters are making difficult but totally unrelated decisions: whether to place a moderately handicapped child in a specialized facility or continue caring for him/her at home, whether to accept a perfect job opportunity on the opposite side of the country or stay and explore a possible-but-uncertain romantic relationship, whether to mortgage the family farm to send one child to college even though doing so puts the rest of the family at risk of losing their home and livelihood. Or a subplot can illustrate the downside of making a hard choice, showing the reader a character trying to recover from the damage done by making the wrong choice…or the right one.

Finally, subplots can provide a change of pace, offering comedy to lighten up an otherwise relentlessly downbeat story or adding a serious thread to a comedy. The scenes of a relatively quiet man-learns-lesson subplot can give readers (and characters, and writers) a place to pause and digest the information that’s been provided by a series of action scenes. Using subplots this way requires careful attention to the internal chronology of the story, for which calendars and time logs/location charts for the characters can be extremely useful. You usually don’t want all six scenes of your quiet subplot to happen over a three-day period at the start of the novel if the whole novel takes six months or a year (though this can work if you have several short subplots that can take place at intervals throughout the year, which can have the same effect as having one long subplot that runs the whole length of the novel).