An American diplomat in China is murdered, and a wealthy Chinese friend of the family raises Mignon, his daughter. When she grows up she wants to return to the US and is tricked into accompanying Foo Shai, a slave trader, to New York. Once there, however, Foo Shai keeps her captive and abuses her. A local artist, Lawrence, falls in love with her, but cannot free her from Foo Shai's clutches. It is up to Chang, a friend of the girl's, to try to help her.