Seeing everything from the protagonist's point of view is not an easy thing; especially if the protagonist is Philip Marlowe, a private detective, who goes through a set of weird situations, some of them involving unusual degree of physicality.
To cut a long story short, I was never punched in the face before. This was the first time in my life, and it was quite upsetting. Even if I didn't actually feel the pain in my face, I was literally taken aback, jumped on my cinema seat dressed in red and shouted. Yes, I was the only one in the audience who shouted, but I am well-known for my unusual degree of identification with two-dimensional heroes and anti-heroes alike.
Mr. Montgomery was successful in his choice of the subjective camera/point of view in what was his directorial debut, Lady in the Lake (1947). An unusual choice indeed, disorientating at times, but it drags you into the action all right. We don't mind at all that the camera itself is the main character, who is in fact visible only in reflections; his hands or other part of his body are visible sometimes, but that's enough. Montgomery is, after all, not the most handsome Marlowe that ever saw the light of day -Humphrey Bogart's representation is unbeatable. Raymond Chandler's book with the same title was good material to start with, even if Chandler himself was not happy with Montgomery's effort to recreate his atmosphere, what's more, without using the script he provided to MGM.
Great experience, good acting from icy slash brainy Audrey Totter -who becomes as tame as a sheep in the end of the film, to my surprise- and a very original and experimental way of filming, that apparently inspired Gaspar Noé in his film Enter the Void (2009). Peter Bradshaw explains it all coherently, even if he snubs the original attempt of the camera viewpoint in favour of the latter. Well, Gaspar Noé is known for treating provocative material, so there's a bigger shock factor there. But, shock factor alone cannot make a good movie, Peter, dear.