Mostly interesting for a peek at China at the time (600's CE), although the author notes in a postscript that he fudged a bit on actual historical details. The writing is easy to follow, but the plot can be confusing. Despite there being two diagrams of the monastery in the printing I read, I found it hard to keep up with Dee as he goes up this staircase, down that corridor, past that room, etc. The story picks up in the last third as clues come together about what is happening.