How to Write Action Lines in a Screenplay

Action lines describe what the audience sees and hears, in present tense, in paragraphs of no more than three or four lines. Write only what can be filmed, capitalise a character's name on first appearance, keep camera directions out of a spec script, and leave white space so the page reads at the speed of the scene.

Updated 2026-09-22 · About 7 sections · 5 answered questions

How to write action lines: the rules in one place

Action lines, also called scene description or the big print, are everything in a screenplay that is not a heading, a character cue or dialogue. They tell the reader what is on screen. The conventions exist because a script is read by people who have to build what you describe, and by readers who have two hundred more in the pile.

Present tense, always. "Mara opens the drawer." Never "opened", never "is opening", never "will open".
Only what can be seen or heard. Not what a character thinks, remembers or used to be.
Paragraphs of three to four lines, maximum. One image or one beat per paragraph. Then white space.
Capitalise a character's name the first time they appear. After that, normal case.
No camera directions in a spec script. No ANGLE ON, no CLOSE UP, no PAN. Describe the image and let the director find the shot.
Cut "we see" and "we hear". If it is on the page, we see it.
Active verbs, specific nouns, few adjectives. "He slams the ledger shut" over "he closes the large old book angrily".

The layout is fixed by the format: action starts at the left margin, runs the full width to the right margin, and is single-spaced with a blank line between paragraphs. Zen Writer sets that automatically as you type, so the rest of this page is about what goes in the lines rather than where they sit. For the full page geometry see screenplay margins and font.

Present tense and the filmable test

Present tense because the audience experiences the film now, not in retrospect. Past tense in an action line reads as a novel; conditional or future reads as a plan. The rule is absolute, and tense drift is one of the first things a professional reader notices.

The second rule is harder to hold. An action line may only contain what a camera could record or a microphone could pick up. That excludes thought ("she wonders whether he knows"), memory ("he remembers the night of the fire"), backstory ("a veteran of two divorces") and intention ("she decides to lie"). Each of those has a filmable equivalent, and finding it is the craft:

WRONG:
Mara wonders whether he knows about the letter.

RIGHT:
Mara watches him. Her hand stays on the drawer.

The second version gives the actor something to play and the reader something to infer. It is also shorter, which is not a coincidence. Unfilmable lines are usually longer because they are explaining rather than showing.

There is a grey zone that experienced writers use sparingly: a line the camera cannot literally record but the audience will read from performance. "He has not slept" is technically unfilmable and universally accepted, because an actor can play it and a reader sees it instantly. Use that licence for one short clause at a time, never for a paragraph.

Paragraph length, vertical white space and pace

Readers read a screenplay down the page, not across it. A dense block of action stops the eye; a column of short paragraphs pulls it. Three or four lines per paragraph is the working limit, and a page with several one-line paragraphs reads faster than a page with two long ones, even if the word count is the same.

Use the paragraph break as an edit. Each paragraph is a shot, or a beat, or a new thing to look at. When the image changes, break. When time passes, break. When a new character enters, break.

INT. NORTH POINT LIGHTHOUSE - NIGHT

Rain hammers the glass. The lamp turns. Turns.

Below, a door bangs open.

ELLIS BRANN (60s), oilskin streaming, hauls himself up the last
of the iron stairs. He is carrying a child's shoe.

He sets it on the lamp housing, where it will be seen from the
water.

Five paragraphs, none over two lines. The white space makes the reader slow down on each image. The same passage written as one block of nine lines would read as a description rather than a sequence of things happening.

Match paragraph length to the pace of the scene. A chase is one-line paragraphs, sometimes one-word ones. A slow scene can carry a four-line paragraph. Do not carry more than that anywhere; if a paragraph runs five lines, it contains two paragraphs.

What to capitalise in action lines

Capitalise	Rule
Character names on first appearance	Always. `ELLIS BRANN (60s)` the first time; `Ellis` after that. See how to write character introductions.
Key sounds	Optional and sparing. `A GUNSHOT.` `The phone RINGS.` Only sounds that matter to the story; a page of capitalised noise stops meaning anything.
Crucial props	Optional and rare. A gun that will be fired in act three, a letter that changes the plot. Some writers never do this; if you do, do it once, on introduction.
Scene headings and secondary headings	Always. `LATER`, `THE KITCHEN`, `BACK TO SCENE` on their own line.
Camera directions and transitions	Capitalised by convention, but neither belongs in a spec script action line.

Capitalising sounds and props is a holdover from shooting scripts, where the sound department and props department scan for them. In a spec script it is tolerated when it draws the eye to something that pays off later, and tiresome when it turns every page into shouting. If you are unsure, capitalise names only. Nobody has ever passed on a script for under-capitalising a doorbell.

The capitalised first appearance is the one that carries weight, because it is also the character introduction. Getting that single line right is a craft of its own, covered in how to write character introductions in a screenplay.

Camera directions, 'we see' and other things to leave out

A spec script is written to be read and bought. A shooting script is written to be filmed. Camera language belongs to the second, and the difference is covered in spec script vs shooting script. In a spec, CLOSE ON, ANGLE ON, PAN TO, WE PUSH IN and POV tell the reader the writer is directing from the page, and they break the flow of the story to do it.

You can still control what the reader looks at. You do it with the order of the sentences and the paragraph breaks. Want a close-up on the shoe? Give it its own paragraph. Want the reveal to land? Put it in the last sentence of the paragraph.

WRONG:
CLOSE ON the child's shoe on the lamp housing. WE PULL BACK to
reveal Ellis watching the water.

RIGHT:
A child's shoe sits on the lamp housing.

Beyond it, Ellis watches the water.

"We see" and "we hear" are the same problem in miniature. Everything in the action line is by definition seen or heard; the phrase adds three words and a narrator. Delete it and start on the subject. The rare exception is a deliberate reveal where the audience's point of view is the point ("We are looking at the wrong door"), and even then most readers would rather you found another way.

Also leave out: music cues (unless the song is in the scene), editing instructions, actor directions in the action line ("she says, angrily"), and anything addressed to the director or the reader. The free spec script checker flags camera directions, WE SEE and similar habits across a whole draft in seconds.

Action line examples: before and after

Three rewrites, each fixing one common problem.

Too much, too slow.

BEFORE:
The kitchen is a large, sunlit room with white cabinets, a
farmhouse sink, a long oak table covered in unopened mail, and
a window looking out over a garden that has clearly not been
tended in some time. MARA (30s), a tired-looking woman with
dark hair pulled back, walks in slowly and looks around at the
mess with a sad expression, remembering better days.

AFTER:
INT. KITCHEN - DAY

Unopened mail covers the table. Through the window, a garden
gone to seed.

MARA (30s) stands in the doorway and does not come in.

The rewrite keeps the two details that mean something and drops the inventory. "Remembering better days" is unfilmable; "does not come in" is the same information as behaviour.

Narrated instead of shown.

BEFORE:
We see Ellis walk to the window. We hear the storm outside
getting louder as he thinks about his daughter.

AFTER:
Ellis crosses to the window. The storm is louder here.

He puts a hand flat against the glass.

Passive and vague.

BEFORE:
The door is opened by a man who seems to be some kind of
official. Papers are handed over.

AFTER:
A man in a county jacket pushes the door open with his
shoulder. He hands Mara a clipboard without looking at her.

Active verbs, a specific noun, one telling behaviour. The reader now knows what the man looks like, what he is carrying and how he feels about being there, in two lines.

Action line mistakes that mark a draft as amateur

Past tense, or tense drift. Present, throughout.
Interior life on the page. Thinks, remembers, realises, decides. Replace with behaviour.
Blocks longer than four lines. Break at every new image.
Camera directions and "we see". Control the eye with sentence order instead.
Capitalising everything. Names on first appearance; sounds and props rarely.
Adjective stacks. "A dark, cold, forbidding, empty room." One precise detail beats four vague ones.
Inventories. Listing every object in a set. Name what the scene will use.
Directing the actor. "She smiles sadly, a single tear rolling down her cheek." Write the situation, not the performance.
Formatting by hand. Spaces and tabs to fake margins. Use a screenwriting app; paste rough text into the free plain text screenplay formatter or open it in Zen Writer for Mac and the elements are placed for you.

Action lines are where a reader decides whether you can write, usually by the bottom of page one. Get the tense right, keep the paragraphs short, and write only what the audience will see. The rest of the craft, from how to write a scene to dialogue and structure, is in the screenwriting guides.

Frequently asked questions

Should action lines be written in present tense?

Yes, without exception. Action lines describe what the audience sees as it happens, so present tense is the only tense that fits. Past tense reads as prose fiction and tense drift within a script is one of the quickest signals of an inexperienced writer.

Is it okay to write 'we see' in a screenplay?

Avoid it. Everything in an action line is already seen by the audience, so the phrase only adds a narrator and slows the line. Start on the subject instead. A few professional writers use it deliberately for point-of-view reveals, but a spec script is safer without it.

How long should an action paragraph be?

No more than three or four lines. One image or one beat per paragraph, with a blank line between them, so the reader's eye moves down the page at the pace of the scene. Fast scenes use one-line paragraphs; if a paragraph reaches five lines, split it.

What should be capitalised in action lines?

A character's name the first time they appear, always. Key sounds and crucial props may be capitalised sparingly, on introduction, if they matter to the plot, but many writers skip that entirely. Camera directions are capitalised by convention and do not belong in a spec script.

Can I write what a character is thinking in an action line?

No. Thoughts, memories and intentions cannot be filmed, so they do not belong in action. Translate them into something the camera can record: a look, a hesitation, an object handled or ignored. The reader infers the thought, which is stronger than being told it.

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Screenwriting Education

How to Write Action Lines in a Screenplay

How to write action lines: the rules in one place

Present tense and the filmable test

Paragraph length, vertical white space and pace

What to capitalise in action lines

Camera directions, 'we see' and other things to leave out

Action line examples: before and after

Action line mistakes that mark a draft as amateur

Frequently asked questions

Ready to turn this idea into a screenplay?

Continue reading

How to Write Character Introductions in a Screenplay

Spec Script vs Shooting Script: What Is the Difference?

How to Write a Scene in a Screenplay:

Screenplay Margins and Font:

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