This was a fun movie to watch and while I admit I went into the movie to see Liu Yifei performance (and she was stunning!) but I stayed and was impressed by the acting of the entire cast.
The movies starts out as goofy and had a satirical tone, which brought quite a few good laughs. It was a good mix of romance and comedy.
The second part of the movie you can see the costumes and production went up a notch and they had a good sense of world building. As If the backdrop of Shanghai city wasn't impressive enough, they created a whole parallel twilight world alongside with it. While the later half of the movie was more of a darker tone, but they still kept a great sense of humor even during some dramatic scenes.
The CGI that was used blended in quite well, and worked to create the fairy tale like world. At times I thought I was watching a Live action remake of some anime serie. I was pleasantly entertained, came to watch Liu Yifei, but stayed for the movie!