Tell the reader what language is spoken and whether the audience understands it, then write the readable translation without repeating the instruction on every line.
Direct answer
When the audience understands the dialogue through subtitles, establish the spoken language in action or with a parenthetical, then write the translated dialogue in the script's reading language. State that it is subtitled when that viewing experience matters. When the audience is not meant to understand, describe the language and the listener's reaction instead of supplying a translation the viewer will never receive.
On the page
INT. NIGHT MARKET - NIGHT
Mara answers the vendor in Mandarin. Their exchange is SUBTITLED.
MARA
Who sold you this watch?
VENDOR
Someone who knew you'd come.
Evidence weight
The screenplay normally stays readable for its intended reader while a concise instruction defines the language heard on screen. The scene should also make clear whether viewers receive subtitles, partial comprehension, or no translation.
Some drafts use a character extension, some use the first parenthetical, and others establish the language in action. All can read cleanly. The important distinction is between the language being spoken and the information the audience receives; typography alone should not be asked to explain both.
Not one rigid template
An action line that establishes the language and subtitles can govern the following dialogue until the language or audience relationship changes.
Use a brief parenthetical such as “in Spanish” when a character switches languages mid-scene or the change could otherwise be missed. Repeating it under every cue adds noise.
If the point is that a viewpoint character cannot understand, describe the speech and any recognizable words or reactions rather than giving the reader a false full translation.
Reader and handoff friction
Choose for the recipient
Write the draft in the language required by the recipient and make any other spoken language legible through a consistent translation convention. Check the current submission rules before sending a multilingual script.
A production draft may add translation, dialect, subtitle, and localization notes outside the reading flow. Confirm final wording with the appropriate language experts rather than treating the submission translation as locked dialogue.
In Plot, keep the translated speech in standard Dialogue and establish the spoken language with Action or a concise Parenthetical. Character extensions remain available for their normal sound-source purpose; language does not require a proprietary dialogue element.
Browse the screenplay formatting reference
Complete, source-backed guides for common screenplay situations
V.O. vs O.S.
Use O.S. for a speaker who belongs to the current scene but is outside the frame; use V.O. when the voice comes from outside the scene's immediate physical action.
Text messages
Put readable on-screen messages in action, identify the sender when needed, and use one consistent pattern instead of disguising silent text as spoken dialogue.
Inserts, screens & written material
Put the exact words the audience must read in action, and use an INSERT only when the change in visual emphasis is itself important.
