After a series of images of rushing water, forest, and dark, empty subterranean hallways, six-year-old Iris arrives topless inside a coffin placed in the dormitory's common area, where she is met with curiosity by the other six girls of the house. After grooming and dressing her, they all exchange hair ribbons with each other – each girl gets the ribbons passed down from the girl a year above her. Iris, the new youngest "red ribbon", excites the ire of Selma, the former red ribbon and now orange ribbon, who complains about absence of the former violet-ribbon Natacha—the oldest who had been her friend. The new violet ribbon, Bianca, takes Iris under her wing. At first Iris is homesick, and believes that she will be reunited with her brother, but Bianca matter-of-factly tells her there is no possibility of that: there are no boys allowed. All of the girls in the school go swimming in the lake, and Iris quickly befriends Laura, the red-ribbon of another house. That night, much to Iris's dismay, Bianca leaves on an authorized mysterious errand that she cannot discuss. The next day, Iris has a routine day at the school – dance lessons, classroom time with animals, and recreation. The classes at the school are run by two pretty young women: Mademoiselle Edith, who walks with a cane and teaches lessons, and Mademoiselle Eva, who teaches dance. Each house is cared for by an elderly serving woman; the girls whisper that all of the employees are girls who tried to escape the walled school in their youth, and were pressed into permanent service as punishment.