[1][2] Alfred Hitchcock's Rear Window, for example, makes frequent use of eyeline matches.
The main character, played by James Stewart, is confined to his apartment and often looks out its rear window at events in the buildings across from him.
Hitchcock frequently cuts from Stewart looking off-screen to various people and events that are assumed to be the focus of his gaze.
Factors influencing the position of the off-camera eyeline (usually by placing the other actors off camera but sometimes by giving the on-camera actor a mark to look at) include the 180 degree rule, camera lens/height/distance to subject and geography of the set.
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