There is a website called TV Tropes, and it has gobbled up more of my time than I care to admit.

TV Tropes is a fascinating and highly informal collection of articles on tropes in storytelling. What are tropes, you ask? A trope is a recurring convention, element or device in a particular genre or type of fiction.

Take horror movies. I’ve never seen one all the way through, but even I know that when the power goes out in a horror film, bad things happen to the person who goes into the basement to check the circuit breakers. Cabins in the woods are dangerous places to be in horror movies, and clowns are evil. We all know these things. They are tropes of the horror genre.

Although tropes are not necessarily good or bad, they can easily degenerate into clichés—conventions that are overused and become trite.

Take the damsel in distress trope: the convention of a female character (often a princess) being rescued by a male character. This trope is everywhere. Consider the Star Wars films, or games in the Mario and Zelda series, or pretty much any animated film produced by Disney. Princesses Leia, Peach, Zelda, Jasmine and Rapunzel are all bona fide damsels in distress.

(I laughed when, in a recent Legend of Zelda game, Princess Zelda—a character descended from a long line of damsels in distress—told the hero, “I will wait for you here. That’s what princesses have always done. From what I understand, it’s kind of a family tradition.”)

While tropes can easily become clichés, they can also be subverted or inverted in clever ways. What happens when the damsel in distress escapes on her own? What if the damsel rescues the hero?

Defying tropes is a wonderful way to surprise readers. We all expect specific things from certain kinds of stories, and it’s a delightful shock to have our expectations shattered.

We’re all familiar with bad guys. Whatever else they may be, they are… well… bad. The trope is simple. Villains are evil. Bad guys are bad. It’s common sense.

Right?

Quite a number of recent films disagree. Despicable Me and Megamind turn villains into good guys. Dr. Horrible’s Sing-Along Blog goes a step farther, making a bad guy out of a “good” superhero. Disney’s Wreck-It Ralph stars a video game villain who decides he wants to be the good guy for a change.

These films toy with our preconceived ideas about heroes and villains, blurring the lines between our notions of “good” and “bad” characters. These films are also tons of fun to watch.

If you’re writing a story, ask yourself: “Has this been done before?”

Working tropes into your story isn’t a crime; some tropes are so general there’s practically no escaping them. In many cases, however, a story can be much improved by avoiding—or defying—the expectations set by all the stories that came before.