Fallen Angels descends straight into the heart of the darkest soul of Hong Kong, trailing the missions of a professional hitman. Wong Chi-ming (Leon Lai) has been in the assassination business for three years, and for him, it's getting old. However, his superior and partner, the elusive Michelle Reis, is interested in keeping him around for more than his killer proficiency; she's secretly in love with him. Unfortunately, Wong is more interested in a fiery-haired woman named Baby. But love will have to wait, as Wong's final assignment will force him deep into the darknesses of both the city and his own soul. Working alongside a mute opportunist, He Zhiwu (Takeshi Kaneshiro), the assassin may survive to the end of the mission, but he must also fight his own disillusionment and despair. Perhaps he will find his new purpose, but it will be a struggle to retain it in the streets of the city that has learned to fear him.