The 180° rule is a cinematography guideline that states that two characters in a scene should maintain the same left/right relationship to one another . When the camera passes over the invisible axis connecting the two subjects, it is called crossing the line and the shot becomes what is called a reverse angle. Reversing the angle is commonly thought to be disorienting and can distract the audience from the intent of the scene. The 180 degree rule is not a law, many notable filmmakers intentionally cross the line to achieve a desired effect that might support the stories narrative.

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