In response to a Japanese user's one star, I think 9 stars is fair.
The spying before WWII from Japan in China was prevalent and nasty. The robbery was under the name "East Asia Coproerisity." The fighting against those invaders had never stopped. (as recorded in history and in the film, the old Shanghai gang people also contributed much in underground acticivities)
I have been consistently shocked by how more and more Japanese people tend to beautify their WWII history since the last decade. If even this film could even hurt their feeling, this film should not be blamed.
This is a film about tolerance and repentance. It is a life story of the hero, it is also a portrait of the culture, or an attitude in the family, friendship and business.
Though I am not a fan of Shanghai culture, I really like the acting. The description of the old Shanghai fashion is really good. Much of the Shanghai culture has been lost since 1949 but some still left. As you can see in the movie, it was very exquisite but life-oriented.