China, 1907. Sixteen-year-old orphan Cassia is sold by her aunt to a brothel. There, she works as a lowly maid for Madame Emerald until a powerful and dangerous client plucks her from obscurity. Master Chang is the boss of the fearsome Shanghai Triad and he always gets what he wants. Despite her unbound feet and breasts, Cassia swiftly becomes Chang's favourite mistress. He showers her with luxuries as he embarks on her sexual awakening. But Chang's world is violent and precarious, and those such as Cassia who depend on him are bound to his fate . . .