Bio-terrorists release a plague in the United States that spreads to kill most of the world's Caucasian population. As the deadly virus mutates, Tzu Shin, a renowned medical doctor and biologist, defects from China to help develop a cure. His only daughter, Lin Kwan, is left behind in Hong Kong with her aunt.

Then Kwan's father summons her from across the sea to bring him Chinese medicinal herbs he needs to develop a cure. Lonely and missing her parents, she accepts the challenge, traveling with her sensei Li Zhong to the New World.

But a Chinese assassin is on her trail, determined to kill her and Li Zhong, and when Kwan discovers her father has disappeared, she sets out on a journey to find him and deliver her precious cargo, a quest that she may not survive.