Dialogue Writing: How to Write Lines That Sound Real

Dialogue writing comes down to subtext: what the characters mean underneath what they say. Good dialogue does two jobs at once. On the surface it moves the scene forward; underneath it reveals something true about the people talking. Bad dialogue does one job, usually the boring one, and the audience can feel the difference immediately.

Good dialogue says one thing and means another. Bad dialogue says exactly what it means and nothing more.

Holmes and Moriarty are never talking about what they're talking about

In Sherlock Holmes: A Game of Shadows, Holmes is, on the surface, a cold selfish man who treats everyone badly, including his only friend Watson. Underneath, he's a deeply caring companion who's terrified that Watson's marriage will cost him his only friend. He never says this. Nobody says it. That's the point.

The film's best scenes are Holmes's meetings with Moriarty. The two men are unfailingly polite. Friendly, even cordial. And every line is a blade. When Holmes mentions that Watson is married now, what he's really saying is: there's no reason for you to hurt him. When Moriarty sends his regards to the happy couple, what he's really saying is: I will kill them both. The true feelings stay under the surface, and because they stay there, the tension grows and grows without ever popping, until the very end.

This is the feel-versus-reveal principle, and it's how real people talk. In real life, nobody announces their innermost feelings. People who care about someone might not show it until they're about to lose them. People who are scared might act like they aren't, to hold their ground. Your characters should work the same way. Write the scene one way on the surface and the opposite underneath, and the audience will lean in to close the gap themselves. An audience that's working is an audience that's watching.

A practical trick: write what the character means first, in plain blunt words, then bury it. "I'm terrified you'll leave me" becomes a joke about the honeymoon. "I will kill your family" becomes regards to the happy couple. The blunt version is your compass; the buried version is your dialogue.

Dialogue writing is voice writing

Subtext is what the dialogue means. Voice is who could have said it.

In Us, the dad has some of the most voice-specific dialogue in modern horror. Packing for the boat: "You got the life preservers. Got that. You have a fire extinguisher. Got that. You have a flare gun. I knew you'd forget the flare gun." Conspiracy theorizing at the table: "Did you know that there's fluoride in the water that the government uses to control our minds?" Nobody else in that movie could say those lines. They couldn't come from the mom, the daughter, or the son. They're his the way a fingerprint is his: funny, a little paranoid, trying too hard to be the capable dad.

Deadpool and Wolverine pushes the same principle to the extreme. Gambit has the craziest accent and dialogue delivery in the film, and it's enough to make a character with no backstory and no journey memorable. Deadpool's whole presence is built on irony: gruesome, disturbing images paired with a light-hearted tone, like dismantling a corpse to the sound of a gleeful pop song. The voice is the character. Change the voice and there's nothing left.

The test I use on my own scripts: cover the character names and read a page of dialogue. If I can't tell who's talking, the voices aren't done. Every person in the room should sound like a different person, because they are one. That is dialogue writing at its least glamorous: most of the work is deleting lines that could belong to anyone.

Then there's rhythm. Short lines create speed and tension; long lines slow the scene down and let it breathe. Watch how a tense scene trades in fragments, interruptions, half-finished thoughts, while a confession scene lets one character finally talk in full paragraphs. The shape of the lines is doing half the acting. When I'm stuck on a flat scene in the edit, half the time the problem isn't what anyone says. It's that everyone speaks in the same rhythm, and the scene has no pulse.

And the trap to avoid: exposition dialogue. Spider-Man 2 is one of the great comic book movies, and even it gets dinged for cheesy, exposition-heavy dialogue. When characters start telling each other things they both already know, for the audience's benefit, the scene dies. Information the audience has to work for is information they'll remember. Information handed to them is noise.

Stop explaining and start implying

The cure for exposition is embarrassingly simple. If both characters already know it, the audience doesn't need to hear it.

Every time I find myself writing a line where one character explains the plan to another character who was in the meeting, I delete it and ask what the scene would lose without the information. Usually the answer is nothing, and the scene gets faster. The practical test: if a line only exists so the audience learns something, find another way to deliver it, because this is show don't tell applied to dialogue. A prop on the table. A look between two people. Half a sentence that assumes the audience is smart. They are. They've watched a thousand movies. Let them fill the gap, because filling the gap is what keeps them engaged.

Key points

• Give every line a surface job and a hidden job; if it only has one, cut it or rewrite it. That is dialogue writing boiled down to one sentence.
• Voice is a fingerprint: cover the names, and you should still know who's talking.
• Rhythm is half the acting: short lines for tension, long lines for weight; never let everyone speak in the same pulse.
• Exposition is the enemy; let the audience work for information and they'll stay awake.
• Read dialogue out loud; if you stumble, the actor will too. What a character won't say is often the most important line in the scene.

Try this

• Watch the Holmes and Moriarty scenes in A Game of Shadows and write down what each polite line really means underneath.
• Take one page of your own dialogue and delete every line that only delivers information; rewrite what's left so the scene still works.
• Give each of your characters one line that nobody else in the script could say; if you can't, you don't know their voice yet.