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.

Follows the lives and families of three adults living and growing up in the United States of America in present and past times. As their paths cross and their life stories intertwine in curious ways, we find that several of them share the same birthday - and so much more than anyone would expect.