It is not only a love movie , but also a Hitchcock-style movie too!
It took me more than one hour to read this loooooooooong post which analyze this movie on on tianya.cn,one of the largest online forum in China:
http://cache.tianya.cn/publicforum/content/filmtv/1/210295.shtml
Too much are hided behind the scenes ... to figure them out you have to watch this movie for more than one time.
some hints:
Mr.Yee's secretary works for Japanese directly, and observes Mr. Yee.
Mr.Yee's driver(the one ) and the middle-aged female servant reports to the secretary actually.
Later in the movie,Mr.Yee actually had become a sort of double-spy.He knew the Japanese is going to be defeated(remember what he said about the Japanese to Miss Wang,aka Mrs. Mai,in the japanese Izakaya?),and started to work for the nationalist party government in Chongqing (remember they mentioned the lost US weapons? why they said the Japanese are looking for the weapons too?)
There were two assassination teams.Because Mr. Yee had turned to the nationalist party government, the original plan to assassinate him had already be aborted(Kuang told Wang that they have to wait for orders,why there were alway no such orders? the students had been given up by the nationalist party government,only they themselves did't know it).
....
BTW, have you noticed that there is a scene in the movie in which a Hitchcock movie poster is shown?
Oh boy,it's time to go back to the theater to solve the puzzles! :)