A lot of rookie screenwriters think they have a great idea for a screenplay.  They might; they might not. For the sake of argument, let’s say a rookie comes up with what he thinks is a really good idea.

He writes a screenplay.  Being inexperienced, he may not know what a really well-executed screenplay looks like. He’ll do his best.

Just finishing a script feels pretty good to a beginner;  regardless of the quality.  So he might be tempted to send his script out to agents and producers in less than great condition.

When the studio readers evaluates your screenplay they may actually be very impressed with your idea.  However, they will notice the mistakes in the script.  Poor dialogue, poor characterization, poor scene choices can wreck a great idea.  Chances are they’re not going to recommend a script full of flaws, no matter how great the story concept.

What happens when you come up with an idea you think is great?  How can you tell if you actually have one?  Well, for one thing, you need a hook. Often a great hook involves a great “what if?”

For example, I sold a screenplay based on a pitch. I thought of a story idea that really appealed to me. It was called “Stepping Out.” DeLaurentis Entertainment Group paid me to develop the screenplay and write it over a six-month period.

What was so great about the idea?  The hero was original, an agoraphobic cartoonist. He had a psychological condition that made him afraid of leaving his house. This is a real condition.

So I started thinking, “what if?” In this case, what if his psychiatrist encourages him to work up all his courage to walk across the street to the park. Baby steps. So, he does. He actually gets his courage up, and walks slowly across the street.

When he gets there, he is so relieved that he finds a bench and slumps down in exhaustion. At that moment, he witnesses a murder. The killer looks right at him, and knows he has to kill this witness.  The killer takes a shot, but misses, however, and escapes.

Now the cartoonist has validated his worst fear. Now he will have to not only leave the house, but will be forced to stay in a series of safe house to stay one step above the killers who want him dead.   That’s the hook, he first ten pages.

So, I had a hook. Even better, I thought about making it a buddy comedy, like 48 Hours. In that movie, Eddie Murphy, is freed from jail temporarily to help solve a crime with a redneck cop, played by Nick Nolte. They were opposites, generally a good fit for a buddy action-comedy.

As they move from safe house to safe house, and are discovered, and have to move some more, the cartooninst is accompanied by a female cop.   She appears to be fearless and takes risks with the cartoonist that he can barely handle. What choice does he have though, if he wants to stay alive?

The ending also occurred to me – this fearless female cop gets stuck with the bad guys and our poor hero has to face his fears and help save her.  In the process he starts to overcome his fears.

When I pitched this idea to my friends, I knew it was good because they could easily see the three-act structure and the change in the characters through conflict. In addition, they got excited about the idea, they offered their own suggestions, and they talked about actors that would be perfect for the lead.

Okay, so that’s how you know you have a great idea.  Is it high-concept?  Meaning, does it feel as exciting? Does it suggest lots of possibilities? Do the characters drive the story? Can people visualize the story based on your pitch? And most importantly, does it have a hook?

Let’s say you’ve created a great high-concept story idea.  Congratulations.  Your idea is great. However, there are still some factors that can hamper your chances of selling.

First problem, what if the movie’s been made already? Or something too similar? Since you haven’t seen every movie ever made, you’ve got to Google the idea. It may turn out that there have been movies based on that idea.

Second problem, movies are being made today, right now, or next year – that you don’t even know about. Look at Variety, Hollywood Reporter, or other sources to find films slotted to shoot soon, or over the next year. Your movie might be coming out in two years.

If a film has been made like just like yours, or even if it’s about to go into production, studios are going to say, there’s already a script like that. Sorry.

Fortunately for me, there were no films made at the time about an agoraphobic murder witness. So, my idea was both great, and original.

There’s another problem with thinking you only need “the great idea” to sell your screenplay. Sure an idea can be great. Most people have at least one great movie idea in them. However, a great idea is one thing.

A great script is another thing entirely. And studios generally are not impressed with a script that’s not well executed, even if it’s based on a great idea.

Remember the other aspects of a great screenplay; it has to have a great hook, a terrific first ten pages, the characters have to be original, interesting and likeable, the story has to be original too, and exciting.  It also needs to be a page-turner, and the scene construction, the dialogue, the pace of the script, the character arcs, and three-act structure need to be strong, without clichés or predictable outcomes, with fresh ideas, and surprising resolutions.

That’s just a brief checklist of what studios are looking for. Yes, everybody likes a great idea. However, the quality of the screenplay will make a big difference.  Now, how do you know how to write a great screenplay?

The way you learn to write a great screenplay is to study, to learn, and to practice.  You’ll need to watch lots of movies, read good screenplays, study screenwriting, write screenplays, ask for feedback from knowledgeable sources, or mentors, or teachers, and rewrite, and rewrite some more.

So you know what to do. Come up with a great, high-concept story idea. Be sure it has a great hook.  Then, be sure you write the best screenplay you can based on your idea.

A great idea alone, will not guarantee a screenplay that will sell.

Image credit: Creative Commons, Red Light Bulb, 2010 by Alex Albian, is licensed under CC By 2.0