Skip to main content

SCRIPT SECRETS: Screenwriting Basics - 2 Plus 2

An artful screenwriter gives the audience the pieces and lets them assemble those pieces themselves. In Script Secrets, William C. Martell shares tips on how to help the audience add up the details for a more rewarding viewing experience.

Click to tweet this article to your friends and followers!

An artful screenwriter gives the audience the pieces and lets them assemble those pieces themselves. In Script Secrets, William C. Martell shares tips on how to help the audience add up the details for a more rewarding viewing experience. 

The Commuter - Lionsgate

"The job of the director is to suggest two plus two. Let the viewer say four," Ernst Lubitsch

That is the job of the screenwriter as well. When you spoon feed information to the audience they know it and feel as if you are treating them as idiots... and feel as if you are manipulating them. Of course, the writers who spoon feed information usually don’t have the skills to manipulate the audience. The writer is a magician, and our goal is to manipulate the audience in such a way that we are never caught. That takes skills, and one of those skills is to give the audience the pieces and let them assemble those pieces themselves. The audience feels in control, and guess who is providing the specific pieces of the puzzle to be assembled? The writer!

Just like any jigsaw puzzle, no matter who assembles those pieces you end up with the picture on the box... and the person assembling the puzzle thinks that *they* made that picture. So "Some assembly required" is a good thing, and a great thing for a writer to use.

Spoilers ahead...

The Commuter (2018) reteams Liam Neeson and director Jaume Collet-Serra (screenplay by Byron Willinger & Philip de Blasi and Ryan Engle) in the story of ex-Police Detective Michael MacCauley (Neeson) who quit the force for a peaceful life in the suburbs as an Insurance Salesman—what could be less exciting than that? He commutes to New York City every business day on the train, with mostly the same passengers who are also commuting to their jobs.

Now, there are a bunch of ways that we might have given the audience this information, but which one would make the audience *feel* those ten years of commuting every day?

The story begins with a montage of those ten years as Michael is driven to the station by his wife Karen (Elizabeth McGovern). He kisses her goodbye and boards the train. Again and again and again. Along the way, things change slightly. Karen is pregnant. Now he has a son, Danny (Dean-Charles Chapman) and we watch the son grow up. The routine is the same, but details change—and that shows us time passing. Michael and Karen get older, too—though less obvious than a kid growing up, but Neeson plays his age in this film. His hair is turning gray. The viewer sees the passage of ten years and experiences the relentless same-ness of the commute. Rain or shine, through ten years, it never changes.

In this montage we are also introduced to some of the regular faces on the train—including Walt (Jonathan Banks) who will figure into the story later. Actually, all of the regulars will figure into the story later—which is another great thing that this montage does—sets up our supporting cast.


Michael’s happy-but-dull routine hits a series of snags. First up: his boss tells him that despite his great work, due to the economy he is being let go—downsized. It’s not his fault, there’s nothing he can do to change things, he’s just out a job.

Now, the audience has seen his wife and son—they have known them for ten years! How do you think this event will make the viewer feel? They add up the family responsibilities and a middle-aged man losing his job and think: How is he going to survive? And the audience feels sympathy for him and cares about him.

Michael needs a drink, and goes to his old haunt—a cop bar—where he bumps into his old partner, Murphy (Patrick Wilson), and his old enemy on the force, Hawthorne (Sam Neill), who has since been promoted to Captain. Michael and Murphy have a conversation about his being downsized—and how he has neglected to phone Karen and tell her. He says he is going to tell her in person... but we get the feeling that he’s just stalling. He doesn’t want to tell her at all. This humanizes him.

[Not So Ordinary – Setting Up the World of the Inciting Incident]

On the train going home, the audience is the now thinking that Michael’s big problem is telling his wife that he is jobless... and that’s when fellow commuter Walt tells him that a woman has been watching him. This creates a few moments of mystery, until Michael sits down and the woman, Joanna (Vera Farmiga), sits with him. The last time I saw a movie with Vera Farmiga and a commuter train, the train exploded every 8 minutes—so this probably won’t end well. Joanna *knows who he is* and *knows everything about him*—creepy! She tells him that he has a particular set of skills that can help her find someone on the train named “Prynne” who is *not* a regular—and there is $250,000 in cash hidden in the train car’s bathroom—a down payment. More if he finds "Prynne" before the Cold Spring Station where Prynne is supposed to get off.

This is a great inciting incident because it is a hook and a mystery—the audience has no idea what this is all about. But we know with that kind of money involved it’s not legal. And we know that Michael is out a job and needs money. What will he do?

2 PLUS 2

Michael goes to the train car’s bathroom, and when he closes the door the light and a fan go on automatically. The fan is at floor level and has a piece of ribbon tied to each side of the grate—but the ribbon is only fluttering on one side... and barely, This place must smell terrible. Michael does a search of the bathroom for the $250,000... knowing that he isn’t going to find it.

Eventually he gets to that fan grate near the floor, unscrews it... and the reason why the ribbons weren’t fluttering? The $250,000 is blocking the vent. Michael looks at the money—will he take it? Will he be part of this probably illegal task?

Michael screws the grate back into place. He leaves the bathroom, but just before he closes the door we see both ribbons fluttering like crazy on the fan grate.

Nothing blocking the vent anymore.

Without ever saying that he took the money, the audience puts 2 and 2 together and gets 4.

[Your Own Devices: How to Keep a Story Moving]

Now we get to the puzzle—who on the train doesn’t belong? First we need to narrow down the suspects, and the clue for that is the Cold Spring Station. Michael consults the map that shows the costs of a ticket for each zone. Cold Spring is Zone 7. The tickets all have the zones punched into them, so now we have narrowed our suspects to those with Zone 7 Tickets.

There is a great shot where the camera shows a Zone 7 ticket and then moves through the punch hole to the passenger’s face. This connects the passenger with the ticket in a visual way—a director’s thing more than a writer thing, but effective.

Throughout the film, the audience is given clues so that *they* can spot the outsider. The audience can even spot the outsider early on, if they are paying attention—a pair of characters switch seats and this leads Michael to think one character who is a Stock Broker may be the outsider because he’s in a seat with a Zone 7 ticket clipped to the seat. That Broker becomes our prime suspect for a while, when it’s the person that they changed seats with who is the actual outsider.


There are other clues where "some assembly is required"—I love the right-handed character who owns a left-handed guitar. And there’s a dialogue-based clue using the word “noble” which points to why Joanna selected Michael to perform this task... and how she knows so much about him. I also love the “red herring” character—a man that Michael (and the audience) realizes does not belong on this train—an outsider! But not the outsider that he was looking for—an FBI Agent placed on the train to protect that outsider... who is a witness in a Federal trial against a mobster. This trial and the witness were planted in the earlier bar scene with Murphy and Hawthorne. Michael suspects that Hawthorne may be working for the mob and behind Joanna selecting him to find the outsider—and that’s another piece of information that the audience is given the puzzle pieces to and assembles it themselves. The clue that leads Michael to the actual outsider—the mystery witness on their way to the trial to testify—is the name “Prynne.” Again, some assembly required, it’s not the character’s name. It’s a code name. The character is reading The Scarlet Letter.

This film is a puzzle, and it plays fair—giving the audience all of the pieces necessary to solve it, but it lets them assemble those pieces. Though the film has a couple of silly parts, it manages to treat the audience with respect—and allow them to put the pieces together as Michael does to find the outsider. Heck, if you are paying attention, you can find the outsider before he does. Act Three becomes a disaster movie, with a runaway train crash that brings rescue crews and the police SWAT team to arrest Michael... who now must figure out how he can prove that Hawthorne is behind all of this before the SWAT Team attacks the train car he is in with “Prynne”... so those audience members who aren’t good at adding 2 Plus 2 will still be entertained. The key to a screenplay like this isn’t to dumb it down so that those who can’t add will get it, but to target both the intelligent audience and the not-so-intelligent audience and entertain both groups. Those who miss the clues will be entertained by the fight scenes and train crash.


Though there are verbal clues like "noble" in the film, most of the 2 Plus 2 elements are visual... because this is a movie. Movies show characters in action. People doing things. A film script is more oriented to showing the puzzle pieces than a stage play, because the audience can see those puzzle pieces. Those little ribbons on the vent would never show up on stage, but film can give them a close up. The hole punches for Zone 7 would never show up in a stage play, either—but we can write a line of action where Michael sees the hole punched in the ticket in a screenplay, and to show the hole the only possible shot is a close up. The camera allows the audience to see things that they could not see on stage, so a screenplay needs to be tailored for that. Focusing on the visual.

[Storytelling Strategies: Sicario’s Vanishing Main Character]

Movies are about people doing things and stage plays are often about people talking about things. Though a movie can feature characters talking—the camera is the "story delivery system" in a film, while the actors deliver the story on the stage. Dialogue-driven stories make better stage plays—film is a visual medium. It's our job to tell the story visually—to create the character actions that will tell the story and the visual clues that allow the audience to assemble the story.

Dialogue in film is usually used as a counterpoint to the action. People usually say one thing and do something entirely different. If a character is afraid, they usually claim that they aren't scared, using false bravado to hide their terror. It's our job to show they are afraid even when they say they aren't. To do that we need to find an action that shows they are afraid, even if they say they aren't. We think that Michael isn’t going to take the $250,000—we know that he doesn’t want to, that he knows this is something illegal that will probably put him and his family in danger. We can show that... and then show the two fluttering ribbons and tell the audience that despite knowing this will cause him trouble, he took the money.


That's one of the major benefits of giving the audience the pieces of the puzzle and allowing them to put them together—instead of hearing about what happened, they EXPERIENCE things happening. When the Tracker figured out where Wilson went, so did the audience! That scene takes us inside the Tracker's mind. When Michael in The Commuter looks at the train map to find out what zone Cold Spring Station is located in, and then looks at the train tickets for ones punched with Zone 7, the audience is inside his mind, thinking what he is thinking. The writer has given the audience step-by-step pieces to the puzzle of how to narrow the “suspect list” and they follow those visual steps along with Michael. The key is to figure out what the steps are and how to show the audience these pieces of the puzzle so that they can assemble them into larger information. This not only “allows the viewer to say four,” it creates audience identification with the character. The audience is thinking like the character because the writer has given them all of the pieces—but the audience believes the character is *thinking like they do* because the character draws the same conclusions from the information.

Of course, all of this begins with the writer giving the audience that information. Two Plus Two doesn’t work if you don’t give the audience one of the Twos. So take care to make sure that all of the pieces necessary to assemble the information are there—and easy enough to spot that the audience in the cinema doesn’t need a pause button. People love to figure things out for themselves, so instead of spoon feeding them information, allow them to add 2 Plus 2 and feel like geniuses when they come up with 4. But also make sure there’s an epic train derailment for the audience members who failed Math in grade school.

The most important thing to remember is to give the audience all of the pieces they need *before* the assembly, so that they *can* assemble them. The Commuter isn’t going to win any Oscars, but that’s the point of using it as an example. This is a basic genre film, and it follows Ernst Lubitsch’s advice. This isn’t some advanced technique, this is one of the basics!

More on this in the Visual Storytelling Blue Book.

More articles by William C. Martell

Download Free Screenwriting Resources! 

Download Now! 

free Downloads!