New York City newspaper writer J.J. Hunsecker holds considerable sway over public opinion with his Broadway column, but one thing that he can't control is his younger sister, Susan, who is in a relationship with aspiring jazz guitarist Steve Dallas. Hunsecker strongly disapproves of the romance and recruits publicist Sidney Falco to find a way to split the couple, no matter how ruthless the method.
China, 1930s, during the ravaging civil war. General Pen entrusts O'Hara, an intrepid American adventurer, with the mission of providing a large sum of money to Mr. Wu with the task of buying weapons in Shanghai to help end General Yang's tyranny that keeps an entire province under his ruthless iron boot.