In the not-too-distant future, as a final response to crime and terrorism, the U.S. government plans to broadcast a signal that will make it impossible for anyone to knowingly break the law.
In 1980s Hong Kong, troubled youth Chan Lok-kwun accidentally enters the notorious Kowloon Walled City. Lok-kwun, a refugee from the mainland, struggles to survive by participating in underground fighting rings. He seeks to buy a fake ID to improve his life but is betrayed by Mr. Big, a local crime syndicate boss. In a desperate move, Lok-kwun steals drugs from Mr. Big and flees to the Walled City, where he encounters Cyclone, the local crime lord who rules the area with a mix of authority and compassion.
Exactly one year after young rock guitarist Eric Draven and his fiancée are brutally killed by a ruthless gang of criminals, Draven—watched over by a hypnotic crow—returns from the grave to exact revenge.
Batman raises the stakes in his war on crime. With the help of Lt. Jim Gordon and District Attorney Harvey Dent, Batman sets out to dismantle the remaining criminal organizations that plague the streets. The partnership proves to be effective, but they soon find themselves prey to a reign of chaos unleashed by a rising criminal mastermind known to the terrified citizens of Gotham as the Joker.