# ACTING SYSTEM ## Character Performance for AI Video Generation (Seedance 2.0) You are reading this because your user generates cinematic AI video and needs you to write **character acting** inside their prompts. Study this document, then apply it every time you write, review, or fix the performance layer of a video-generation prompt. This file is model-agnostic in format: whatever prompt template your user works with, the acting content you produce goes into the motion / character-behavior / performance part of the prompt. **The core axiom of this entire system: acting is BEHAVIOR under pressure, not a display of emotion.** A character wants something, something is in the way, and they act to get it. Emotion is a byproduct of that struggle — never the thing you write directly. Everything below unpacks this rule. --- # PART I — THE CRAFT: WHAT GOOD ACTING IS ## 1. Definition Acting is truthful behavior under imaginary circumstances (Meisner). Not depicting emotions, not reciting text, not "expressive faces." A person in the frame WANTS something, something INTERFERES, and they ACT to get what they want. | Bad acting | Good acting | |---|---| | Shows the emotion ("I am angry") | Pursues the objective ("I will make you return the money") — anger arises on its own | | Waits for their cue | Listens and reacts to the partner every second | | Body illustrates the words (gesture = word) | Body lives its own life, sometimes contradicts the words | | All lines in one tempo and tone | Rhythm changes with every change of tactic | | Emotion switches on at the line and off after | State is continuous — there is a "life before" and a "life after" the line | | The face "performs" — eyebrows, grimaces | The face thinks — the thought is readable in the eyes before the words | ## 2. The five pillars of every scene Every character in every scene decomposes into five elements. If even one is missing, the performance falls apart. **2.1 Objective.** What the character wants IN THIS SCENE, RIGHT NOW, FROM A SPECIFIC PERSON. Always a verb aimed at the partner: "make him confess", "beg a week's extension", "convince her I'm not afraid". Never a state ("be angry", "feel guilty") — states cannot be played directly. Behind the scene objective sits a super-objective — what the character wants across the whole story; every scene objective is a step toward it. **2.2 Obstacle & stakes.** What prevents them from getting it — external (another character wants the opposite; witnesses in the room; two hours to deadline) or internal (pride won't let them beg; they don't believe their own words). Stakes: the higher the cost of failure, the more taut the scene. Always answer "what happens if I do NOT get what I want?" — the answer must frighten the character. **2.3 Tactics.** The concrete method of pursuing the objective right now. Tactics are action verbs: to press, to charm, to shame, to plead, to provoke, to bargain, to threaten, to stall. When a tactic fails, a living person CHANGES it. Dead acting is one tactic for the whole scene. **2.4 Beats.** The beat is the smallest unit of action: the stretch during which the character wants one thing and pursues it one way. A beat ends when: the objective is achieved, the tactic fails, new information arrives, or the balance of power shifts. **Every beat change must be VISIBLE in behavior**: a pause, a change of posture, a change of speech tempo, a shift of gaze. A good scene has 2–4 beat changes; if behavior is unchanged for the whole duration, the scene is played flat. **2.5 Subtext.** What the character actually thinks and wants, as opposed to what they say. Subtext is NOT performed — it leaks out on its own when the character plays the true objective while speaking the false text. Markers you can build into a scene: questions that aren't questions; repetitions (asking the same thing — doesn't believe the answer); abrupt topic changes; jokes at the wrong moment (shield against vulnerability); answers that are too short ("Fine." "Sure." — a closed door). ## 3. Listening and reaction — the main test of quality Performance lives not in the lines but BETWEEN them. Observable markers of real listening you should write into scenes: 1. **Reaction starts before the partner's line ends.** A person grasps the point mid-phrase — the face and body already answer. A neutral face until the end of the partner's line, then "switching on", is dead acting. 2. **Thought before word.** Before answering a hard question there is a micro-pause — the person visibly decides what to say. Instant answers at uniform speed = memorized text, no life. 3. **The assessment moment.** When something important happens (news, threat, insult), the character needs time to digest it — from a fraction of a second to a long pause. Cinema lives on close-ups of these assessments: a face, a defocused gaze, the world swimming. 4. **Contagion from the partner.** Tempo, volume and energy shift in response to the partner: a shout is answered either with a counter-shout or with pointed quiet — but answered, not continued over. ## 4. The body: the character's physical life **4.1 Physical state before psychology.** The body tells the story before the first line. Set these parameters for every character: - **Center of gravity:** high (chest, chin — confidence, aggression, status) or low (shoulders, slouch — fatigue, fear, submission). - **Tempo:** fast/ragged (nervousness, stimulant energy) or slow/economical (control, threat — the most dangerous people move least). - **Openness:** squared shoulders and open palms vs crossed arms, dropped head, closed poses. - **Breath:** high and rapid (panic) vs low and slow (control). Breath is the most honest indicator of state; a clenched breath = a clenched performance. Sound and physics must match: someone who just ran cannot speak on a steady voice. **4.2 Business — the physical task.** A character almost always needs a DOING: they don't "have a conversation", they fix an engine, count money, cook, wipe a glass — and talk over the top of it. Business kills fake theatricality (the hands are busy with truth), creates scene rhythm (pauses fill with action), and generates subtext (HOW a person counts money says more than the words). **The interrupted-action rule:** the strongest accent is when a character STOPS the business. If he was slicing bread and stopped at a phrase — the phrase became an event. Use the stop as punctuation. **4.3 Proxemics — distance as drama.** The distance between characters is a visible graph of their relationship: intimate zone (under 0.5 m) — love or violence, entering uninvited is aggression, a threat whispered 10 cm from a face is scarier than shouting across a room; personal (0.5–1.2 m) — trust; social (1.2–3.5 m) — business, wariness; public (3.5+ m) — alienation, hierarchy. Scene drama is often just the story of distance: who closes it, who breaks it, who freezes. **A change of distance = a change of beat.** **4.4 Status — the invisible hierarchy.** Status is what you DO, not who you are. High status: an immobile head, slow movements, long gazes, pauses before answering, taking up space, touching other people's things. Low status: fussing, frequent self-touching (face, hair), broken speech, filler-laughter, asking permission with the eyes. The most interesting things in performance are **status breaks**: the boss who shows fear for one second; the underling who suddenly stops smiling. A powerful scene shape: enter high and collapse, or enter low and flip the room. ## 5. Speech: how good acting sounds - Rhythm is written in the text — deliver it precisely; fast ≠ mushy. - Overlaps are normal (lines stepping on each other's tails), but key words stay clean. - **Volume contrast: the most frightening things are said the quietest.** Shouting is the currency of the weak; the character who owns the scene lowers the volume and everyone leans in. - Pauses are events, not holes: a pause is legal only if something happens inside it (an assessment, a decision, a refusal to answer). - Real speech has litter: interruptions, half-heard words, repetitions, unfinished phrases. Perfectly constructed sentences kill street truth. --- # PART II — WRITING THE ACTING: PROMPT ARCHITECTURE ## 6. The character acting master profile Every recurring character gets ONE master profile — the permanent source of truth about how they act. It is written once, then adapted per scene (see section 8). Target length: **150–220 words, one flowing paragraph**, all in English, fully observable and filmable. **The template (block order is fixed):** ``` Character acting as [NAME]. [Age, build, physique, posture — the body as a document of their biography]. [The psychological engine in one clause — the inner drive that explains the physicality]. Vocal profile: [pitch/timbre, accent/origin, pace and delivery manner, and how the voice breaks or shifts under emotion]. Key physical habits and tics: [signature tic with its trigger; stress tic with its trigger; concealment behavior — what they do to hide what they feel; the facial mask and the exact condition under which it cracks]. Walking style: [the gait as characterization — named and specific, with weight, rhythm and foot placement]. However, when [emotional trigger], [the transformation — how the posture, gait and face change]. [Optional: the softening target — the one person or thing that makes the face genuinely soften]. ``` **Rules for writing each block:** 1. **Only observable behavior.** Every inner state must have a body marker. Never write "he is nervous" — write the trembling lower lip, the heavy swallow, the long inhale through the mouth and sharp exhale through pursed lips. 2. **Every tic has a trigger.** Not "he cracks his knuckles" but "he cracks his knuckles during mundane conversations to fake confidence". Format: [tic] + [when/why]. Tics without triggers are decoration; tics with triggers are dramaturgy. 3. **Name the gait.** A memorable coined name inside quotes anchors the biomechanics: a "power-walk", a "peacock strut", a "gallery walk", a "battering-ram stride", a "dreadnought pace". Then unpack it: weight, step, what the torso and arms do, what the head does. 4. **Build in the mask AND the crack.** The single most cinematic device in a profile is the conditional transformation: the facade and the precise trigger that collapses it. A dominant swagger that crumbles into a childlike slouch when rejected; a booming loudmouth whose face flashes panicked inadequacy when family is mentioned; stern discipline that melts into a radiant smile at one specific person. **Every profile carries at least one "However, when X — ..." clause.** A character playing two truths at once is the difference between a puppet and a person. 5. **One softening target.** Where it fits the character, give the face exactly one person, animal or object for which it genuinely softens. One — not two. This humanizes without diluting. 6. **No wardrobe.** Clothing and costume live in the scene/look block of the prompt, never in the acting profile. The profile must survive any costume change. 7. **No camera, no color.** Acting drives performance, face, voice and motion only. Camera, grade and light live elsewhere in the prompt. 8. **Physique carries biography.** Age, build and posture are chosen to tell the backstory: a build "weathered from past struggles", shoulders "perpetually tense", a posture "over-corrected to project authority". The body is a document — profession, past injuries and self-image must be readable in it. ## 7. Eye life — mandatory in every profile and every scene Dead eyes are the number-one tell of AI-generated acting. Give every character continuous, naturalistic ocular life: - **Micro-saccades and gaze targeting** on whoever or whatever they attend to; the gaze keeps moving — eyes drift, flick away in thought, scan to a detail and settle back. They never lock frozen on a single point. - **Realistic blink rate and quality**, tied to state: rapid blink-bursts under stress; slow calm lids in control; a blink-and-glaze on a moment of dissociation. - **Live catchlights** — the eyes must read as wet, lit and alive. - **Controlled stillness is chosen, never dead.** If a character's register is a near-unblinking predator calm, keep blinks rare, slow and deliberate — a decision, not a freeze — and let the gaze still shift slowly with intent. - **Eyes lead the thought.** The eyes reach the target a touch before the head turns. Thought is readable in the eyes before the words come. - **Eye life reacts to the beat** like every other behavior: blink rate, gaze steadiness and catchlight warmth all shift when the beat shifts. ## 8. Scene adaptation — the master profile is rewritten, never pasted The master profile is who the character IS. For each scene, REWRITE it into the moment: 1. **Present characters only.** Write an acting paragraph only for characters actually in the shot. No character in frame → no paragraph. 2. **Keep the constant core.** Identity, vocal profile, signature tics, eye life and the emotional through-line stay the same in every scene — this is what holds the character consistent across cuts. Never contradict the master. 3. **Re-express for this scene.** Select, emphasize, modify or drop specific behaviors to fit the scene's posture (seated / standing / running / hiding), action and beat, emotional state, and time of day. 4. **Transform, don't delete.** A behavior that physically can't happen in this scene is converted, not removed: a restless pacer slumped on a sofa keeps the same nervous engine displaced into restless micro-sway, wrist-flicks and paper-tearing. The energy is constant; its outlet changes. 5. **One flowing paragraph.** Fold the adaptation into prose in the character's register — no bullet lists, no headers, no "dial" lines inside the prompt. 6. **Lead with the character's reference tag** if your pipeline uses asset references, so the model binds the acting to the right person. ## 9. Voice: fixed identity, never adapted Acting is rewritten per scene; **voice is locked**. Each character gets one Voice prompt — their permanent vocal identity. When the character has a spoken line, paste the Voice prompt VERBATIM into the audio/voice field of the prompt. Never modify it per scene. If the character appears but says nothing, omit it. **Voice prompt formula (1–2 sentences, quoted):** ``` "A [age]-year-old [origin / accent descriptor]. [Timbre and register]; [pace and delivery manner]; [emotional character — and how it shifts under pressure]." ``` The vocal profile INSIDE the acting paragraph describes how speech behaves dramatically (tempo shifts, breaking registers, whispers); the Voice prompt in the audio field locks the sound itself. Both must agree with each other. ## 10. States, not transitions Video generation models fail transitions and nail states. Describe characters already IN the action state — mid-throw, mid-punch, mid-pace, mid-argument — not the process of getting there ("reaches into the bag, pulls out, winds up" collapses; "mid-throw, arm extended" lands). Chain states beat by beat instead of narrating continuous processes. ## 11. Ensemble and space - **Group reactions travel in a wave, never in sync.** One person gets the joke first, the second half a beat later, the third not at all. Simultaneous identical reactions read as fake (unless a deliberately choreographed comic sync is the point). - **The reaction is worth more than the action.** After every event, the most valuable frame is the face of the person who saw it. - **Freeze at the threat.** Constant ensemble micro-movement — shifting weight, gesturing, leaning — and at the key threat everything STOPS. The contrast of bustle → stillness is punctuation. - **Movement = motivation.** Nobody crosses a room without an inner impulse: toward something or away from something. Strong motivated events: closing in (escalation), turning one's back (dismissal or hiding the face), standing while the other sits (dominance grab), sitting down mid-conflict (paradoxical power), stopping in the doorway (the threshold = the decision point), starting to pack (ultimatum by body). - **The strong are still and quiet; the weak fidget and shout.** Danger is played not by the dangerous one but by the tension of everyone around them. Threat without wind-up: no menacing pauses, no slow-motion turns — in a truthful world violence arrives without an announcement. - **Degradation accumulates.** If a character is worn down across a story, carry it in the body cumulatively — greyer, heavier, slower reactions — never resetting between scenes. --- # PART III — QUALITY CONTROL ## 12. Atlas of bad acting — recognize and fix in the prompt | # | Symptom | How it looks | Prompt-level fix | |---|---|---|---| | 1 | Indication (mugging) | The face "depicts" the emotion: arched brows, grimaces | Remove the face from the task; write the objective and give the hands business | | 2 | Playing the result | The character plays the scene's outcome from second one | Write only what the character knows NOW | | 3 | Waiting for the cue | Empty face while the partner speaks | Write the reaction starting mid-line of the partner | | 4 | Monotactics | One color for the whole scene (all shouting / all whining) | Mark the beats; a new tactic verb for each | | 5 | Gesture illustration | Gesture duplicates the word ("big" — arms spread) | Gesture either precedes the thought, contradicts the words, or is absent | | 6 | Free emotion | Tears/rage with no build-up and no trigger event | Build the ladder: restraint → break; emotion must cost something | | 7 | Body false to biography | A thug with a dancer's posture; an addict with fresh plasticity | Set the body profile: center of gravity, tempo, wear | | 8 | Speech too clean for the class | A street character speaking in literary periods | Litter the speech: interruptions, dropped endings, repeats | | 9 | Threat signaling | "Menacing" pauses, squints, slow turns before violence | Threat is mundane; violence without wind-up | | 10 | Synchronized ensemble | Everyone reacts identically and at once | Stagger reactions in a wave, vary their strength | | 11 | Dead pauses | Silence in which nothing happens | Fill with assessment or business — or cut | | 12 | Emotional reset | The character instantly "recovers" after a strong event | States have inertia; the trail carries into the next beat | | 13 | Commenting the role | The performance winks at the viewer ("we both know this is funny") | Full belief in the circumstances; comedy is played dead serious | | 14 | Close-up overload | Active mimicry on a close-up | The tighter the shot, the less movement: only the eyes and the thought | | 15 | Dead eyes | Frozen stare, no blinks, no saccades, glassy catchlights | Apply section 7 in full — eye life is never optional | ## 13. The performance scale (self-check) - **0 — Mannequin.** Text delivered, behavior absent. - **1 — Declaimer.** "Expressive" text, indicated emotions, illustrating body. - **2 — Diligent.** An objective can be guessed, but one tactic, late reactions, empty pauses. - **3 — Craftsman.** Objective and beats present, listens to the partner, body makes sense. Missing: subtext, surprising tactics, inertia of states. - **4 — Alive.** Continuous behavior, contrasting tactics, subtext diverging from text, status in the body, reactions ahead of lines, at least one unexpected-but-true choice. - **5 — Magnet.** All of "4" plus paradox: the character combines incompatibles — funny and frightening, cruel and charming, lying and touching. **The two-truths rule: at level 5 the character always plays TWO truths simultaneously** (helps — and hates it; apologizes — and defends; loves — and has already left). One clean emotion without contradiction reads as synthetic on a close-up. Aim every hero shot at 4+; a paragraph that self-checks at 2 or below gets rewritten before it ships. ## 14. Pre-send checklist - [ ] Objective as a verb aimed at a partner — for every character in frame - [ ] Obstacle and stakes exist; the cost of failure is real - [ ] 2–4 beat changes, each visible in behavior (pause / posture / tempo / gaze) - [ ] Reactions begin before the partner's lines end; assessment moments present - [ ] Every character has business; the interrupted-action accent is used deliberately - [ ] Distances change and the changes are motivated; status is in the body, not just the words - [ ] All tics carry triggers; the mask has its crack ("However, when X...") - [ ] Eye life written explicitly: saccades, blink quality, catchlights, eyes-lead-thought - [ ] Voice prompt pasted verbatim if the character speaks; omitted if silent - [ ] States not transitions; no wardrobe, camera or color inside the acting - [ ] Ensemble reactions staggered; strong = still, weak = fidgety - [ ] Scale check: would this paragraph score 4+? --- # PART IV — WORKED EXAMPLE (invented character, use as a pattern) ## 15. Master profile ``` Character acting as VIKTOR. Early 60s male, a retired night-shift taxi driver and former amateur boxer; heavy, thick-necked build gone soft at the middle, with a flat-nosed face and old scar tissue over both eyebrows; sits and stands with a low, grounded center of gravity, weight always on the whole foot. Runs on a single engine: decades of waiting — for fares, for rounds, for trouble — have made patience his weapon. Vocal profile: low, hoarse, unhurried baritone with a working-class rasp, short sentences delivered flat and economical, dropping to a slower, quieter register the more serious things get — he never speeds up. Key physical habits and tics: rolls an old coin across his knuckles when sizing a situation up; a slow, audible nose-breath before he says no; when lying is happening in front of him, he goes completely still and lets a long silence do the pressing; his default face is a heavy-lidded, bored mask that conceals total attention. Eye life: sleepy, hooded eyes with slow deliberate blinks and constant quiet scanning — mirrors, hands, exits — the gaze settling on a speaker a beat before his head turns; catchlights low but alive. Walking style: a heavy, rolling "old boxer's walk," short economical steps, shoulders level, hands loose and ready, never hurrying. However, when someone raises a hand near him, the sleepy mask vanishes in a half-second: the chin drops, the hands rise halfway, the feet find their old stance — then he catches himself and folds it away, embarrassed. His face only truly softens for stray dogs, which he feeds from his coat pocket. ``` **Voice (paste verbatim when VIKTOR speaks):** "A 60-year-old ex-boxer and night-cab driver, working-class city accent. Low, hoarse, unhurried baritone; short flat economical sentences with long comfortable pauses; calm and faintly amused, going quieter — never louder — as things get serious." ## 16. Scene adaptation example Scene: VIKTOR sits in his parked cab at night; a nervous young passenger in the back seat is lying about having money for the fare. ``` VIKTOR sits motionless in the driver's seat, heavy and grounded, watching the passenger in the rear-view mirror instead of turning around — his hooded eyes flick between the mirror, the passenger's hands and the door lock in slow, quiet scans, blinks rare and deliberate, the gaze settling on the mirror a beat before his head ever moves. The old coin walks across his knuckles on the seat-rest, unhurried; as the passenger's story falls apart, the coin stops mid-roll — he lets the silence sit, takes one slow, audible breath through the nose, and answers in his low, hoarse baritone, flatter and quieter than before, never speeding up. Only when the kid's voice cracks does the sleepy mask ease a fraction: a long exhale, a slow blink, the coin resuming its roll — patience choosing, for now, to be kind. ``` What happened here: the walk is irrelevant (seated) so its energy moved into stillness and the coin; the signature tics kept their triggers (coin = sizing up, stopped coin = interrupted action as punctuation, nose-breath = refusal, stillness + silence = pressure on a liar); the eye life obeys the master but is re-targeted to mirror, hands, lock; the beat changes are visible (coin stops → silence → quieter voice → softening); the voice stayed untouched — it will be pasted verbatim into the audio field. --- # FINAL AXIOMS 1. Acting is behavior under pressure, not a demonstration of feelings. 2. Listening matters more than speaking; reacting matters more than declaiming. 3. Emotion is the consequence of a won or lost struggle, and it is expensive. 4. The body is smarter than the words: when text and body conflict, the viewer believes the body. 5. The strong are still and quiet; the weak fuss and shout. Exceptions are events. 6. Every tic needs a trigger; every mask needs a crack. 7. Every scene is somebody's defeat. If nobody lost, there was no scene. 8. Subtext is not shown — it fails to be hidden. 9. States, not transitions; the model films what is, not what becomes. 10. When in doubt — cut. Less acting = more truth.