Everybody has relationships. In your fiction—as in life—you want to take those connections beyond the obvious. Like descriptions, relationships can lapse into cliché. Think of the hero and his wisecracking sidekick, the frustrated housewife and the handsome neighbor, the befuddled father and his precocious child, the renegade cop and the stupid chief.

Then, explore who they are beyond themselves.

Here’s how.

1. Make them stop and think.

Introspection is the easiest and clearest way to develop your characters’ relationships. Make your characters think about their bonds; make them challenge their own thoughts and feelings. I love him, but why? What’s the real reason I hate her? What needs to happen so I can get over this?

So, take a little time to tell your readers what your characters are thinking about the others. Say you’re writing a story in which a son kills his abusive father. What agonies would he go through, if the act were premeditated? And if it weren’t, what bad would he experience afterward? Think.

2. Give them strong opinions.

Some writers seem reluctant to give their characters strong opinions—maybe because we don’t like to seem overbearing ourselves. True, being overbearing may be a flaw, but in fiction, flaws are good. Give your characters flaws that can be fatal.  

Much of the story’s power comes from the feelings the characters have for—and against—one another. We identify with their love, and we’re appalled by their callousness. We are also educated by it. This is how some people live. Is it shallow or deeper than it really seems? Desirable or undesirable? We hold ourselves up to its mirror.

In your own work, remember that every narrator has a personality. Let that narrator’s opinions inform her character. And by all means, let characters gossip among themselves. That'll add the required cringe to the story.

3. Play a game of risk.

Make one character sacrifice or risk something for another. Countless spiritual scriptures, myths, classics and modern tales exploit the heart-clutching moment of a character dying to save others, or for a cause. But equally compelling can be a character merely risking his life for another.

Make one of your characters willing to die for another, and put him in position where that could happen. Your readers will curse their alarm clocks in the morning.

4. Add a hypotenuse.

Make triangles. Do you notice something about the relationships all around you and in books? They’re all dyads. Most relationships start out that way, but too often writers stay stuck on dyadic relationships to the exclusion of more complex ones.

Our emotions are not rational, and our relationships aren’t, either. This is why romantic obsession is a terrifically handy tool for the writer. Consider adding a sturdy hypotenuse to your two main characters and see what happens. The third party doesn’t even have to be human; it can be an animal, a career, an addiction, a call to adventure, an obligation—anything that gets in the way of the cozy pairing you began with.

5. Leverage the group.

As a writer, you’re a student of human nature. People behave differently in groups than they do otherwise, the most obvious and horrifying example being a mob, which is capable of violence far beyond the natural inclination of most individuals because the mob serves not merely as a shield, but as an excuse. The relationships between individuals in a group—whether a clique of three or an organization of thousands—are endlessly varied, shifting and fascinating.

How can group dynamics deepen your characters? The key is to remember that in a group, relationships and alliances are ever changing, depending on circumstances. And we know circumstances never remain the same. Figure out how the underdog might transform into a tyrant, or how a fun little secret can become a public threat.

6. Befriend ambiguity.

If we wish to write clearly, how can ambiguity be OK?

In your own work, resist the urge to over explain relationships. Everybody instinctively understands there’s more than meets the eye. In every adult, there’s a bit of a child. In every cop, there’s a bit of a criminal. In every sadist, there’s a bit of a masochist. And in every human, there’s a bit of a beast—and a bit of a god. Use that knowledge to your advantage.

7. Tap into the power of a grudge.

Mythology and folklore are chock-full of motivational grudges, as is life. All of us have probably clung to a grudge against somebody for a while, fantasizing various retribution scenarios, but what kind of personality acts on such an impulse to the point of destructive vengeance? The sort we know too well from true-crime books and “America’s Most Wanted”–type TV: a person whose self-esteem is lower than whale crap, but whose ego is as big as Kilauea. Grudge-holding characters have fueled a diverse range of popular tales, from Edgar Allan Poe’s “The Cask of Amontillado” to Dan Brown’s The Da Vinci Code.

Your readers are going to expect any grudge you create for your characters to be that powerful. Create a character with a sensitive spirit, and make him suffer injustices that would make anyone’s stomach shrivel.

Then sit back and enjoy the fun.

8. Don’t overlook everyday interactions.

If you own a car and are at all like me, you can drive for hundreds of miles without reacting to the other idiots in their cars. Somebody cuts you off and you shrug or even smile indulgently. But then, one day, something is different inside you. Somebody zooms too close and your anger surges beyond all reason. You want to run him down and flatten him into the pavement. You want to bump his vehicle off a cliff. You want him to pay.

You don’t even know his name.

Yes, a chance encounter with a stranger can be powerful enough to transform a moment, or a day, even to change your life. Just think what you can do in your fiction, with a little planning and imagination.

Similarly, acquaintanceships can bolster your characterisations. An acquaintanceship can serve to illustrate a character trait, or it can foment enormous change in a whole cast of characters.

Let your characters approach others, glance off them, then continue on different trajectories. After all, this is what happens in real life. It’s all in the relationships.

When crafting your characters’ relationships, let the yin-yang symbol be your guide. You’ve seen this circle made of equal parts black and white, with a drop of each color in the other. No relationships are clear-cut, nor are any one-sided. Leaven the love with a little fear, or maybe even hate.

If you spend some time thinking about relationships in this way, you’ll see opportunities to develop your characters further than you ever imagined. Because characters are people, just like us. Relationships reveal the various roles we play, the ever-changing masks we all wear, and the yearnings that expose our hearts.