I've read Raymond Chandler's "The Long Goodbye" and thoroughly enjoyed it. What makes Philip Marlowe such an appealing character is that underneath his cynical exterior is a man who is a romantic. He's a nice man caught up in a sleazy, amoral world.
Unfortunately, Robert Altman completely misses the point of Marlowe's character in this film. While I can respect wanting to take a new approach to a well-worn genre, Altman's sneering contempt for Chandler's detective ruins what could have been a truly great movie. Elliott Gould too often comes across as a goofy smart-... who seems to think he is too cool for the role he is playing.
Unlike the genre-busting "M*A*S*H" and "McCabe & Mrs. Miller", Altman completely strips the characters in this film of any humanity. There is not one character in this film that is even remotely likeable.