Land of Silence and Darkness (original title: Land des Schweigens und der Dunkelheit) is a 1971 documentary by the German filmmaker Werner Herzog which asks deaf-blind people about their experience of life.
The film centres around Fini Straubinger who lost both her eyesight and hearing at an early age. She describes how it happened and how she has lived with such a terrible affliction.
This was one of Herzog's' earliest documentary films, having only made a couple before Land of Silence and Darkness. Before those, he mostly made short fictional movies, the earliest of which was made in 1962.
Of course, this film is in German so to watch The Look of Silence with English subtitles click the cog on the bottom right of the player > subtitles > auto-translate > English. It is not ideal but it is the only way to watch it online legitimately for free. With that said the Youtube engine does a remarkable job, even translating German text on the screen.