In New York City in the 1910s, Luella and Effie Tildon realize that even as wealthy young women, their freedoms come with limits. When the sisters discover a shocking secret about their father, Luella, the brazen elder sister, becomes emboldened to do as she pleases. Her rebellion comes with consequences, and Effie suspects her father has sent Luella to the "House of Mercy." Effie gets herself committed to save her sister, but when Effie's own escape seems impossible she must rely on an enigmatic girl named Mable to survive.