I've read a number of screenplays from newbies in which two main characters are best friends who agree on everything. It often seems as if the only reason there are two characters in those scripts is so they have someone to talk to as they explain the plot to the reader with on-the-nose dialogue.

The importance of conflict in every scene cannot be underestimated. But sometimes writers think of conflict only in terms of the antagonist. Characters who get along can still have conflict.

Take a look at Callie Khouri's Oscar winning debut script, Thelma & Louise, for example. Spoiler alert: I'm going to discuss plot details, so if you haven't seen it yet, really? This movie is old enough to vote.

Thelma and Louise are best friends who are always on the same side and always have each other's back. But right from the beginning, Louise (Susan Sarandon) has an underlying frustration with Thelma's naivety.

Thelma (Geena Davis) wants to stop and have some fun on the way to the cabin. Louise doesn't. Conflict. Thelma wants to drink and dance. Louise warns her not to get into any trouble. Thelma doesn't listen and gets herself into real trouble out in the parking lot. Louise has to rescue her by shooting Harlan, setting them both on the lam.

Later, Thelma wants to pick up J.D. (Brad Pitt). Louise doesn't think it's such a good idea. Thelma gets her way and J.D. steals Louise's money. A setback for both of them. They're in it together but they got there through conflicting goals and attitudes every step of the way.

From that point on, their roles switch. Thelma robs a liquor store while Louise waits in the car, unaware. Thelma forces Louise to confront a dark, repressed memory. Thelma gets them away from a cop who pulls them over for speeding after Louise has run out of ideas. And Louise is the one who slips and lets the FBI find them, while Thelma wonders if her friend is considering giving up.

Each protagonist has her own distinct arc. Thelma begins as a sheltered idealist, while Louise is a hardened realist. By the end of the picture, the BFFs are square on the same page. They make their final and hardest decision together, in absolute unity.

When writing buddy characters, make sure they have fundamentally opposite qualities, like Oscar and Felix, and imbue every scene with conflict that grows naturally from those differences.

Dan Margules is a Los Angeles based screenwriter and a board member of the Scriptwriters Network. His award-winning short film, Begleiter, is loaded with conflict and available in a Special Edition from Amazon.com or happy-the-dog.com.