I never heard of a Mary Sue character until last week, and now it seems as if everywhere I go online I run into an article about Mary Sue or her male counterpart Marty Stu. These highly idealized characters are often author wish-fulfillment, being unrealistically bright, beautiful, and able to do anything. Though the author considers the characters to be perfect, they are not. In fact, I’m not certain it’s possible to write an unflawed character, because the arrogance of perfection is a flaw in itself. Mary Sues are annoying, which is another flaw. And Mary Sues are flat. Physically, of course, they are curvaceous or muscular or both, but they are uninteresting. Which, of course, is another flaw.
To me, a purposely flawed character is just as bad, an anti-Mary Sue. If a character is well drawn, if the story is well told, the flaws will show up naturally. A character must lose occasionally. Where is the suspense if every time a character attempts to do something she succeeds? And in that loss is a shadow of the flaw, because the loss must be realistic. Did the character lose because of arrogance, assuming she knew what to do when she didn’t? Did the character lose because she wasn’t physically fit or knowledgeable enough? Did the character lose because she didn’t plan correctly, because she was unfocused, because of her inner conflicts?
Losses force a fully-realized character to change so in the end she can succeed. A Mary Sue doesn’t change. She cannot become more perfect, and if she becomes less perfect, she becomes flawed and stops being a perfect character.
Depth of character is revealed in the choices someone makes under pressure. Pressure is risk. Risk is conflict. Mary Sues, being perfect, do not feel pressure, do not truly risk since they cannot lose. Without the element of risk, without conflict, there is no real story, only a string of episodes. Just think what Superman would be like without his Krytonite — totally uninteresting and flawed in his perfection. But Kryptonite, to me, is a purposeful flaw, put there to make Superman more interesting, which makes him seem even more of a comic book character. Oh, wait. He is a comic book character!
So, to keep your story from being comic-bookish and to keep your characters from being Mary Sues, put your characters under pressure, give them much to lose, and let them change because of their experiences. Then you will have a perfect character: someone real, someone empathetic, someone to remember.