A woman desperate for a child weaves one out of hair, with unsettling results. In "Wild," a disastrous night out shifts a teenager and her Nigerian cousin onto uneasy common ground. In "The Future Looks Good," three generations of women are haunted by the ghosts of war, while in "Light," a father struggles to protect and empower the daughter he loves. And in the title story, in a world ravaged by flood and riven by class, experts have discovered how to "fix the equation of a person," with rippling, unforeseen repercussions.