shot reverse shot is a film making technique to show a conversation between two people, typically showing a back and forth between one person talking and then the other. however, it can instead show the reaction as the other person talks. As it is filmed over the shoulder of one character it is assumed that the characters are facing each other.
it utilises the 180 degree rule, the eye line match, and rule of change among others. Film historian David Bordwell defines the film technique “wherein one character is shown looking (often off-screen) at another character, and then the other character is shown looking “back” at the first character. Since the characters are shown facing in opposite directions, the viewer unconsciously assumes that they are looking at each other.” (Bordwell)
The primary elements of a shot/reverse shot sequence are derived from the three-camera set up. The shots you should have for a basic shot reverse shot are: a two-shot of the characters usually in wide or medium shot; an over the shoulder shot on character A; and an over the shoulder shot on character B. The diagram below should give you an idea of the set up.
This technique is instrumental for Hollywood’s classical editing style, as it typically provides continuity in conversation with characters filmed at eye-level. It is meant to immerse audiences in the dialogue – and thus the story – instead of directing their attention to the visual style. Shot reverse shot originally served this type of “invisible editing”, never calling attention to itself and staying within the bounds of continuous time and space. But filmmakers have also discovered ways of dramatically enhancing shot reverse shot, through stylistic means that are a little more pronounced.