Some screenwriting books advise you to create your story and then worry about theme after your story has been written. That might work, except you risk writing a story that isn’t integrated so then you wind up trying to create a theme out of a sprawling story. A better solution is to think of your theme first and look for a universal truth that resonates with everyone.
For example, “Rocky” was about an underdog struggling for a chance, which is what everyone dreams about. “Alien” was about the fear of the unknown personified by the alien. “Avatar” was about harmony with nature. “Titanic” was about living your dreams.
When you have a strong theme from the beginning, it makes it easy to make sure your story reinforces that theme instead of ignoring it or contradicting it. Just look at the greatest movies of all time and they have a strong theme. “Casablanca” is about finding your true calling. What makes a theme especially appealing is when we can see and experience the massive change the hero undergoes. We aren’t just spectators watching a movie. We’re actually living the emotions of the hero as he or she struggles to achieve a goal. By the end of “Titanic,” you may not have survived a sinking ocean liner, but you do feel exhilarated to do the best with your own life afterwards. When movies have a strong, universal theme that an audience can experience, it makes a movie great. When a movie lacks a strong theme, all the action and special effects in the world can’t save it. Just look at the difference between the original “Star Wars” and the three awful prequels. Strip away the theme and just show action and you’ve basically given us junk food instead of a substantial meal.
So how do you create a theme with a universal truth? First, think of your own dreams, hopes, and fears. Romantic comedies always tap into our emotions because we all want to find love. Horror scares us because we all are afraid of something. Comedies make us feel good because we all like to laugh. So the best way to create a universal theme for your story is to first identify a strong emotion in yourself. Now look at your story and ask yourself if your story idea evokes a strong emotion. If not, then you may need to tweak your story idea.
Take a bland movie like “Captain America” and compare it to the first “Thor” movie. In “Thor,” the hero has to learn humility, which is a lesson everyone needs to learn at times. In “Captain America,” the hero just wants to be a soldier. Not much emotional response there. To tweak “Captain America,” imagine if the hero wasn’t just a scrawny kid, but someone who got picked on and ignored, who felt the sting of rejection from women because he’s too skinny, who constantly sees his dreams dashed because he’s too weak. By giving the hero a little more emotional motivation, “Captain America” could have gotten closer to tapping the universal truth that everyone feels inferior and would love a magic transformation that could make us stronger than everyone else.
Your hero doesn’t just need a goal, but also a motivation. “Kill Bill” is easy to understand because if someone tries to kill you, you’d want to get revenge. Blake Snyder in “Save the Cat” says that the best stories are understandable by a cave man because that taps into our deep emotional needs. Revenge is easy for a cave man to understand along with love (romantic comedies), fear (horror), and drama. Would a cave man understand the theme of “Titanic” to live your life to its fullest? Probably. Would a cave man understand the goal of the hero to be a soldier in “Captain America”? Maybe, but the emotional impact is far less. A cave man might understand the desire to be greater than you currently are, but “Captain America” doesn’t quite do that.
Remember, in the old days when primitive people sat around campfires, telling each other stories, they didn’t do it just for the entertainment value alone (which is like loading a movie hip with special effects and lots of explosions) but to teach a lesson or explain something in their own lives, such as how the Earth was formed or how the leopard got its spots. Such stories remain memorable because they try to explain our lives so we better understand our place in the universe.
Boil your story down to its essence and ask if a cave man would understand the universal truth your story is trying to tell. If not, then rework your theme under a cave man could understand it. The motivation of your hero needs to be understood by a cave man. When you can do that, then you’ll likely get an audience to feel emotionally moved by your story as well.