The pebbled glass door panel is lettered in flaked black paint: 'Philip Marlowe...Investigations'. It is a reasonably shabby door at the end of a reasonably shabby corridor in the sort of building that was new about the year the all-tile bathroom became the basis of civilization. The door is locked, but next to it is another door with the same legend which is not locked. Come on in - there's nobody in here but me and a big bluebottle fly.