If you’ve not seen Enter the Void, then you should.

‘Gaspar Noé planned it over a period of 15 years - before his short film Carne. He was around 23 years old, when he saw Robert Montgomery’s Lady in the Lake while on drugs. The film is shot in subjective camera, entirely from the point of view of the main character. For Enter the Void, Noé uses a subjective camera in the same manner. The main character Oscar is seen just once while the character is alive, in a mirror.’
(Source:IMDB)