So sorting out the storyline to The Big Sleep will get you nowhere.

There are viewers who are easily annoyed by logical inconsistencies in movies. The noir/gothic position is - or should be if it isn't - that the universe doesn't make any damn sense anyway, so don't come to some director working under all kinds of constraints and ask him or her to sort it out for you. The best he or she can do is demonstrate what life in the maze feels like as opposed to what it is. Sometimes, bless their hearts, they do take a shot at it - what it is, I mean - but when it comes to that - when it comes to truth - they don't know any more than you do. Physicists might. Try one of them.