How does theme fit into your story? I’ll answer the question with another question: what happens to your character in the course of your story?
Well, you say, she is a shy, withdrawn, CIA analyst who must go into the field to thwart the sale of a nuclear detonator to a terrorist group. She is a fish out of water in an exotic foreign country but overcomes her social awkwardness to thwart the terrorists in the nick of time.
So, your theme could be believe in yourself, or facing your fears, or never give up. I’m sure you could thing of some better ones. The point is that theme flows from your hero’s change as she progresses through the story. This is called character arc. How does character arc work? The hero bumbles and stumbles through the story, having setbacks and learning from them then having epiphanies and moving forward. And your theme is expressed through your character’s journey through the story.
Basically, theme and character arc are closely connected. With no theme and character arc you have no story, or, at best, extended water cooler gossip. Remember, your theme and character arc come about through that old adage on writing, “show, don’t tell.” In my novel, The Peril Protocol, the hero, Hope Allerd, must find a serial killer. She’s initially motivated by her hatred of a petty thief who murdered her parents and what he represents. As the story progresses, she slowly realizes that only by forgiving can she move forward and release the burdens of her past.
But, wait, you say, what about the series character such as James Bond or Jack Ryan. They never change or grow. That’s what makes them iconic. And you would be right. Although, there is no character arc for these heroes, you can still find a theme. The obvious one is good always conquers evil.
However, series characters can still have a character arc according to Larry Brooks in his book , Story Engineering. If you don’t believe it just visit a brick and mortar or online comic book store. More likely than not, you’ll find a superhero such as Batman or Spiderman in an angst filled situation such as having to murder his best friend in order to save the world. That’s just dripping with theme.
Find the theme in your novel. It’s not that difficult. As a writer you merely have to present the question, its up to your readers to provide the answers. After all, theme is a matter of opinion. And there’s no rule that says you have to have only one theme.
Theme is an important part of writing. It makes your story one that your readers will be sure to remember.