This book was shelved in mystery, but it read to me more like a fantasy novel that used the tropes of detective stories as an endlessly malleable playground.  The main character, Charles Unwin, is easily likeable, as he moves through the story hopelessly in over his head.  The set pieces are beautiful, even haunting.  I enjoyed the first two thirds of the book more than the ending, in which the amorphous dreamlike reality Unwin has been cast into solidifies into a literal, structured dreamscape.  The plot, while reasonably satisfyingly resolved, just isn’t as compelling as the images and atmosphere.  For most of the book the story feels like a dream, in that even when there are moments of danger and uncertainty, there is no sense of menace: in the end, we will wake up safe in bed.  As the story moves toward the climax it embraces more traditional forms of narrative tension and suspense, and starts to feel somehow flatter for it.  Still, even if the plot seems slight in retrospect, the characters are delightful and each gets his or her moment to shine before the end.  This was a highly enjoyable read, and a perfect book to keep on the bedside table, get lost in under the covers, and fall asleep while reading.