One of the most crucial aspects of a script is the storyline. The storyline is the thread that holds together the fabric of a screenplay, weaving color and texture in and out of scenes in intricate patterns that come together to tell a story. A compelling storyline keeps audiences glued to their seats. It's a careful mix of tension, action, suspense, and mystery that is meant to keep the audience thinking and their adrenaline pumping. Even in more lighthearted stories, there needs to be a sense of excitement and the unexpected. In order to successfully write that mix, your script needs to have a strong plot and subplots. Alfred Hitchcock was a master of plot and suspense and could keep an audience mesmerized from fade-in to fade-out. As a filmmaker, hooking an audience should be one of your goals, but it takes plenty of skill and artistry and a clever script.

The Plot Thickens

Concocting a plot that is original yet commercial is no easy feat, especially if you're appealing to a wide audience. Scripts that contain too many plot twists tend to confuse people, and scripts that don't have enough plot turns tend to bore people. Scripts that can pull off a big shocker can often prove successful. Kevin Costner's 1987 role in No Way Out, for example, is a great example of this. By film's end, no one saw the left hook coming. The same goes for the big reveal in director Neil Jordan's The Crying Game, and more recently in M. Night Shyamalan's The Sixth Sense. In 1973, audiences were shocked by Charlton Heston's horrifying discovery in the futuristic thriller Soylent Green. Suspense built slowly throughout the film until its conclusion, when Heston yelled the now infamous “Soylent Green is people!”

Structure in Three Acts

Screenplays, no matter the genre, are held together by a three-act structure — a beginning, middle, and end. The divisions are commonly referred to as acts. It's important to note that in the grand scheme of screenwriting, there is a common denominator in that the majority of films have a main character who must face some form of opposition that by the third act is brought to a resolution.

Act one establishes your environment and primary character, or protagonist, describing and showing who that character is and what she hopes to achieve. Act two expands your character by focusing on what she's going to do to reach her goal, the forces that provide opposition in the form of an antagonist, and the revelation that results after confronting obstacles she must overcome. Act three focuses on resolution of this character's journey — a payoff of all the suspense, drama, conflict, and characterization you've built throughout the first two acts. As one act ends and another begins there is always a moment of drama or action that turns the plot. Those apex moments that signal a shift from one act to another are called plot points.

Character Development

Character development is the lifeblood of any story, whether small screen, wide screen, stage, or literary in form. In order to create a character, you need to start with the basics. How old is your character? What does he look like? What are his habits? Is he intelligent or dim? Where did he come from? It's essential that you ask yourself all of these questions before you start writing. Establishing a character's background, approximate physicality, and personality is crucial. When brainstorming a character's traits you'll find the true nature of your character emerging, and can then begin tailoring your character's role as hero, villain, comedian, killer, ingenue, and so on.

Creating Conflict

A story is nothing without some form of conflict, be it subtle or grandiose. Every protagonist needs an antagonist. Think of it as the battle between good and evil, two forces in constant opposition that taunt each other until they finally come to blows. Every story needs that pull in a consistent manner in order to keep the plot interesting and entertaining. Conflict can come from a character, force, disability, flaw, misunderstanding, disaster — any number of worldly and otherworldly situations.

No matter whether you're writing the script or you've hired a writer, it's important that everyone is clear on the protagonist's initial conflict, how it builds throughout the script, and how it's ultimately resolved. In any film that you view, you should be able to recognize the conflict and the steps taken to resolve it.

For example, in the 1987 film Fatal Attraction, Dan Gallagher, played by Michael Douglas, has a one-night stand with Glenn Close's character, Alex Forrest. It's a prime setup for conflict because Dan is married. The conflict begins to build as Alex becomes obsessed. She stalks Dan, then squirms her way into Dan's unknowing family. As her paranoid personality grows stronger, she kidnaps Dan's daughter. By the conclusion, the conflict has exploded and she attempts to kill Dan's wife.

The Hero's Journey

One of the more historically successful structural elements is known as “the hero's journey.” For as long as people have told stories and throughout motion picture history, audiences have witnessed the triumphs and travails of characters ranging from Charlton Heston's Moses to Katharine Hepburn's Rose Sayer, and from Indiana Jones to Neo of The Matrix trilogy. Heroes and heroines are mystical, dramatic, courageous, virtuous, and moral. They always do the right thing, and audiences love them.

When writing a hero's tale it's important to remember that his journey is central to the plot. His impetus and motivation is what keeps the storyline consistent and interesting. You want your audience to feel the range of emotions your hero feels, endure his hardships, and stand up and cheer when he finally achieves his goals.

The hero's journey has been written over and over again and in myriad genres. As far as concepts go, it's nothing original. The twist you give it can be unique, so think outside the box. Heroes come in all shapes and sizes and ages, but if there's a single film that sets the mark for a hero's journey, it is George Lucas's Star Wars.

Throughout the Star Wars franchise, and especially in the first three movies, Luke Skywalker epitomizes the definition of hero. The screenplay for Star Wars is often used as a benchmark for new writers, and for good reason. Skywalker faces every conflict in the book: good versus evil, selfishness versus selflessness, friendship versus romance, war versus peace, and ultimately father versus son. And he must face it all on an interstellar level.

Writing a hero's journey requires careful study of how your character will think, act, react, and treat others, and what he will do to get to journey's end. You want audiences to cheer and not be apathetic about a hero's success.

Subtext and Backstory

A script, whether it's commercial or artistic, must have depth. Revealing what lies just beneath the surface is an aspect of storytelling that should be mastered by both writer and filmmaker. Whether you reveal a character's thoughts and motives directly or indirectly, through action, flashbacks, or subtitles, it's crucial that the audience becomes privy to certain facts about your characters. That means subtext and backstory.

Subtext refers to the underlying content of your story, and it can be used in many ways. It can throw a thin veil over a film's political undercurrent, in or cast a light on a character's true motivations. Many period films such as Sense and Sensibility and Remains of the Day are seething with sexual repression. The Batman mythos makes great use of the murder of Bruce Wayne's parents as having created his vigilante alter ego.

Moment by Moment

Audiences flock to movies for all kinds of reasons, the most obvious being that they want to be whisked away from their daily existence to explore a new world, experience a love affair, laugh hysterically, or feel the thrill of an action-packed adventure. As a filmmaker, and certainly as a writer, one of your greatest hopes is that after an audience's temporary vacation from life, they will remember certain special moments.

These moments could be a look, some action, or a bit of dialogue. Key moments, whether poignant, humorous, terrifying, or ironic, can make a film memorable rather than forgettable. Sometimes it's the payoff for a long harrowing experience — for example, when Roy Scheider aims his rifle at the great white killing machine in Jaws, or when William Hurt discovers a yearbook picture in Body Heat.

Many of what are considered to be classic films contain such moments and are written in such a way as to become legendary. Humphrey Bogart in Casablanca cooing “Here's looking at you, kid” and Tom Cruise telling Renee Zellweger “You complete me” in Jerry McGuire are examples. Another would be Hannibal Lecter taunting neophyte FBI agent Clarice Starling, saying, “Tell me Clarice, have the lambs stopped screaming?” in The Silence of the Lambs. Those are moments frozen in time that leave an audience feeling satisfied at film's end.