This review will be a little vague to prevent spoilers :)
The story is based on a Chinese fairy tale about a cursed boy and spirit/demon pearl. The movie as a whole was very enjoyable and well made visually and in composition. I found the pacing very good and that the viewing was a consistently enjoyable experience.
i would summarize the movie as a Wuxia action movie interwoven with great humor. Definitely a must see.