Rack focus
Shifting focus within a shot from one subject to another. The director choosing where you look without cutting.
The rack focus redirects attention inside an unbroken shot: the plane of sharpness travels, near face to far door, letter to reaction, and the viewer's eye is escorted from one meaning to the next without a cut's punctuation. The shot revises its own subject midsentence.
Choosing where you look without cutting keeps both subjects in the same continuous space, which is the figure's power: the connection between them is shown, not asserted. It demands shallow depth and an exact pull, and it must be motivated, an unearned rack reads as the film clearing its throat. Design borrows the idea whenever emphasis shifts within a persistent layout.