This document lists and summarizes 10 of Alfred Hitchcock's most essential films, according to common themes in his work including ordinary people in dangerous situations, shifting allegiances, and the use of "MacGuffins" or plot devices. It discusses Hitchcock's directorial style of focusing on emotional impact over plausibility and his collaborations with composer Bernard Herrmann. The 10 essential films are ranked in reverse order, with Strangers on a Train ranked as Hitchcock's greatest film.