There's a whole subgenre of detective stories where the detective is our guide through the surreal and dreamlike, through psychological or magical oddness. While tempting and often worthwhile, it imposes a whole set of new requirements on both the mystery and fantasy. This work is solid in many areas - especially in the consistency of the strangeness and the rules of the fantastic.  But in the characters, it falls short. We need to have highly grounded characters, relatable people who do things for a relatable reason, so that we understand their paths through the strangeness. We don't quite have that here. It's the only thing holding this back from being a true classic.