This was a difficult film for Yimou Zhang to make. His relationship with his leading lady Gong Li was coming to an acrimonious end and the Chinese authorities were deliberately hassling him with complicated and elusive work permits. That was mainly because they were still annoyed with him for submitting his previous film To Live (1994) to the Cannes Film Festival without their permission.
Savvy viewers would notice that the physical appearance of gangland boss Tang was modeled on that of former China ruler Chiang Kai Shek, arch enemy of the Communists.
In the final scene on the boat back to Shanghai from the island, the gang boss jokes that the grass will be good on the island next summer. This is a subtle, morbid joke referring to the fact that the many people they killed and buried there will decompose and fertilize the soil, making the grass better there the following summer. In the context of the film, it demonstrates once and for all how evil the gang is.