Confused yet curious, six-year-old Iris is taken in hand by Bianca, the leader of a group of girls who live in one of five houses that make up a kind of boarding school. The only adults are old servants and two authoritarian teachers. Obedience is paramount. Those caught trying to escape are either swallowed up by the horrors of the outside world or condemned to serve the other girls within the school walls for the rest of their lives. The girls suffer various indignities of school life, longing to get outside. However, the eldest girls disappear each night for several hours under orders not to reveal their whereabouts to the others. In the end, we learn how these girls step into adulthood in this familiar, but clearly alternate, universe.