### 180‑Degree Rule

> The camera must stay on one side of an imaginary line (the **axis of action**) so that left and right remain consistent for the viewer.

> This is not The Matrix, you are not one of the Wachowskis.

Note:
Introduce the idea of spatial grammar; viewers build a mental map within seconds. Violating it breaks immersion.


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180‑Degree Rule
<img src="images/30-180-degree/180-degree-rule.png" alt="Illustration of the action axis with safe camera positions" />

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180‑Degree Rule
#### The Axis of Action

* Subject A always screen‑left, Subject B screen‑right.
* Any camera placed within the 180° arc keeps this orientation.

Note:
Point to coloured semicircle on slide—explain that this is the camera's “safe zone.”

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#### What Happens If You Cross?

* Subjects swap screen sides → confusion.
* Eyelines no longer match → broken eye contact.
* Movement direction reverses (car appears to turn around).

Note:
Play a 5‑second clip of a conversation where one shot accidentally crosses; ask the room what feels “wrong.”

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#### Three Ways to Cross Cleanly

1. **Neutral (on‑line) shot** – cut to a shot that sits directly on the axis, then to the new side.
2. **Visible camera move** – dolly/pan across the line within a single shot.
3. **Subject movement** – have the actor walk across the axis; cut once they’ve settled on the other side.

Note:
Emphasise that each method gives the audience a visual “ticket” allowing the flip.

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#### Breaking the Rule — Deliberately

> Rules are guidelines; break them with intent.

* Fight chaos, dream logic, psychological disorientation.
* Use colour or lighting cues to anchor geography even when L/R flips.

Note:
Show quick montage from "The Bourne Ultimatum" to illustrate purposeful disorientation.