The Moment: Police detective Scottie Ferguson (James Stewart) gives chase across the rooftops of San Francisco, but fails to apprehend his target - and sees a fellow officer die in front of him - when his vertigo gets the better of him.
Why It's Great:
A short, sharp shock of an opening sequence that is all the more effective because Hitchcock leaves Scottie dangling at the scene's end, setting up the film's dreamlike ambience. Also, of course, there's the small matter of the
shot: Hitchcock's innovative combination of a tracking shot and zoom.