# Emotion as behaviour

People and places / Expression / Direction rules. Checked 2026-10-13.

Acting that reads as real instead of a generated face pulling an expression.

- Use when: Every prompt with a person showing a feeling.
- Phrase: describe one body part per beat with a trigger: at the sound of the door her smile drops and her shoulders go still
- Page: https://directorchair.ai/expression/emotion-as-behaviour
- JSON: https://directorchair.ai/api/expression/emotion-as-behaviour.json

## Watch out

- Never write he is sad. Write the eyes, the jaw, the breath, with the moment that causes it. (practitioner; Dan Kieft via Director Chair field notes on video prompting)
- Never ask for a smile or for an emotion by name; describe the muscles. Asked-for smiles come back generated and forced. (measured; Director Chair field notes on video prompting (client feedback, Aug 2026))

## Prompts

### Nano Banana Pro

```
[your subject] in [your setting]. Describe one body part per beat with a trigger: at the sound of the door the subject's smile drops and the subject's shoulders go still.
```

### Nano Banana 2

```
[your subject] in [your setting]. Describe one body part per beat with a trigger: at the sound of the door the subject's smile drops and the subject's shoulders go still.
```

### GPT Image 2.5

```
A photograph of [your subject] in [your setting].
People and framing: describe one body part per beat with a trigger: at the sound of the door the subject's smile drops and the subject's shoulders go still
Exclusions: no extra text, no watermark, no logo.
```

### Seedream 5

```
[your subject] in [your setting]. Describe one body part per beat with a trigger: at the sound of the door the subject's smile drops and the subject's shoulders go still.
```

### Seedance 2.5

```
Scene: [your subject] in [your setting].
Shot 1 (0:00 to 0:05): describe one body part per beat with a trigger: at the sound of the door the subject's smile drops and the subject's shoulders go still
```

### Seedance 2.0

```
Scene: [your subject] in [your setting].
Shot 1: describe one body part per beat with a trigger: at the sound of the door the subject's smile drops and the subject's shoulders go still
```

### Kling 3.0

```
[your subject]. Describe one body part per beat with a trigger: at the sound of the door the subject's smile drops and the subject's shoulders go still. The scene is [your setting].
```

### Veo 3.1

```
[your subject] in [your setting]. Describe one body part per beat with a trigger: at the sound of the door the subject's smile drops and the subject's shoulders go still. Framing and subject stay as in the start image.
```

## Look further

- https://seedance-emotion-direction.vercel.app/ : a clip of this emotion performed in Seedance 2.5 (link only)

## Goes well with

- No default smile: https://directorchair.ai/expression/no-default-smile
- Sadness: https://directorchair.ai/expression/sadness

## Source

Rules from Director Chair field notes on video prompting

Text CC BY 4.0, Director Chair (directorchair.ai). Reference clips and their card texts belong to their makers.