The story is told from the perspective of Dede (Dedé Mirabal), who is the only sister who survived the brutal murders of her three sisters. The novel primarily focuses on the lives of Minerva, Patria, and Minerva's husband, Manolo, during the dictatorship of Rafael Trujillo in the Dominican Republic.
The novel explores the lives of these women, their activism against the regime, and their tragic fates.
It's important to note that the novel's title refers to the sisters themselves: Minerva, Patria, and Maria Teresa were nicknamed "Las Mariposas" (the butterflies) by their friends because of their grace and beauty.
The story uses the sisters' lives as a metaphor for the delicate beauty of freedom, which is easily crushed by oppression and violence.