What really creates added tension and suspense isn’t more violence, sex, or special effects, but relationship triangles. This occurs when two people want something from the same person. By creating a relationship triangle among your characters, you increase tension and suspense because audiences want to know who will win in the end.
In romantic comedies, there’s always a hero looking for true love, the wrong person for the hero to love, and the right person for the hero to love. The tension comes when the hero has to choose the right person but is often coerced into choosing the wrong person. That wrong person doesn’t need to be evil or nasty, just not the right person for the hero. In “Sleepless in Seattle,” the hero is starting to get close to a woman who really likes him, but the hero’s son doesn’t think this woman its right for his dad.
The hero is mostly pursuing this other woman because she’s available and he’s lonely. The hero really needs to find his true love, but she’s a woman he doesn’t know and who lives clear across the country. The tension pulling the hero to the wrong person and keeping him from the right person creates conflict far more interesting than adding more plot twists could ever do.
Even in “Star Wars” there’s a simple relationship triangle between Luke and Hans Solo, who both like Princess Leia. Even though this relationship triangle is never fully resolved, it still adds tension between Luke and Hans.
Relationship triangles don’t necessarily have to be between people but between choices. Make the easy choice the wrong option and make the right choice the hard option and now the hero is torn between taking the easy way out or working hard to get what he or she really wants. In “It’s a Wonderful Life,” the hero is torn between killing himself so his family can collect his life insurance policy, or facing the threat of going to jail for losing his savings and loan’s money. This tension between two choices keeps a story interesting because the audience always wants to know which choice the hero will take.
In “Platoon,” the hero is a young soldier who has to deal with a friendly leader and a more vicious one. Both leaders protect the hero but when the hero sees the vicious leader has wounded the friendly leader and left him to die, then the hero finally has to choose what he will do. The easy choice is to do nothing. The hard choice is to confront the vicious leader.
So make sure your story has a relationship triangle either between people or hard (right) and easy (wrong) choices. Relationships triangles create suspense that strengthens your story.