A crime she committed in her youthful past sends Piper Chapman to a women's prison, where she trades her comfortable New York life for one of unexpected camaraderie and conflict in an eccentric group of fellow inmates.

The daily lives of prisoners in Emerald City, an experimental unit of the Oswald Maximum Security Prison where ingroups - Muslims, Latinos, Italians, Aryans - stick close to their mutual friends and terrorize their mutual enemies.