I won't take you through the plot, others before me have done a much better job than I could do. What I want to do is give you feeling of this book.
If you're looking to use this story as a reference to Chinese mythos, you may well be wasting your time; there are elements of the mythology here but they've been used as a basis rather than adhered to stringently. They give the story its reason to be though.
This is ostensibly a love story, written with a huge sense of humour and tongue in cheek at the amount of violence the characters use to achieve their ends. Its a fantasy story and needs to be taken as such; read it without a sense of humour and you will be disappointed. There's a quiet joy involved in reading this book. It's total escapism from cover to cover, and one of those stories that you'll come back to when you're feeling low or want to run away from reality for a while.
I've yet to read the sequels as I didn't know they existed till I came here to replaced my much-loved but lost copy of this book. I'm over-joyed that there are two more Master Li books for me to find, and gutted to know that the author felt he'd taken the characters as far as he could with this trilogy. I'm sure he ended on a high though.