Mary’s mother decides to join the Unconsecrated. Mary is allowed to wait with her mother until the woman dies. The two are separated by a wire fence, with her mother restrained in a pen. Once dead, her mother will be dragged outside by a rope. It takes a day for Mary’s mother to die, as the bite was small. Cass comes to visit Mary during the vigil but ultimately cannot face the horror of watching the woman’s death, so she leaves.

Just before dawn, Mary’s mother frantically tells Mary that the ocean is beautiful and that something is “consuming” her. Then she dies, and a Guardian pulls her outside the fence. Jed, who has finally arrived, calls for Mary, and she goes to him.

According to custom, Mary must bathe in holy water, then stay in an isolated room at the Cathedral for a week. Sister Tabitha, who is the head of the Sisterhood, claims that this is the only way they can be sure that Mary will not intentionally allow herself to be bitten or decide to let the Unconsecrated into the village. Mary’s room overlooks the fence and pen where her mother died, and while she is there, Jed never visits. At the end of the week, feeling no belief in God, she is released.

At home, Jed demands to know why she did not choose to have their mother killed, as he will now be forced to do so if he sees her. Mary tells him that it was their mother’s choice to join the Unconsecrated. Jed refuses to listen because he is angry and grieving—not only because their mother is gone, but also because Beth has lost the baby. Jed tells Mary that Harry has not “spoken for” her. (In other words, Harry has not indicated any intention to wed Mary). Jed tells his sister that he does not intend to take her back into what is now his home—not even until next fall, when someone else might speak for her. As a result, Mary’s only remaining avenue is to become a Sister, and this realization shocks her.

Before Mary returns to the Cathedral, she climbs to the top of the hill above the village because she wants to see the whole enclave: the village, the farms, the surrounding forest, and two paths, one to either side of the village, that lead out of the fenced enclosure. The paths themselves are fenced and protected from the undead, but using these paths is forbidden. They have grown over with brush, and no one recalls where they lead.

When Mary returns to the Cathedral, the Sisters are expecting her. Sister Tabitha asks Mary if she has chosen the Sisterhood, and Mary says she has no other options. Sister Tabitha takes Mary through a dark stone tunnel under the building. She explains that the Cathedral used to be a winery, and the tunnel allowed workers to take freshly stomped wine to the storerooms. At the end of the tunnel, Sister Tabitha forces Mary to surface through a small door into a tightly fenced ring. The Unconsecrated swarm around her immediately, only steps away. A nearby rope would easily open a gate, leaving Mary defenseless. Sister Tabitha tells Mary that joining the Sisterhood must be a conscious choice. Mary frantically agrees, claiming that she chooses this path willingly. Sister Tabitha takes Mary back to the same room that she vacated earlier and instructs her to remain silent and to read the Scripture five times.

Still grieving her mother, Mary spends weeks alone, reading and rereading the Scripture. Winter sets in, and one night, a patient arrives at the hospital section of the Sisters’ Cathedral. He screams in the night.

Sister Tabitha brings Mary to the newly arrived patient the next morning. It is Travis. He has broken his leg badly. As time passes, Sister Tabitha consistently allows Mary to visit Travis, but Mary cannot bring herself to pray. Instead, she whispers to him about the ocean. Within a short time, Mary falls in love with Travis.

Cass and Harry arrive to visit Travis. Mary is jealous when Travis, who is ill with fever and infection, seems to push his head against Cass’s comforting hand. Harry explains that Jed found Travis in a field and took him to the Cathedral, but no one knows how Travis broke his leg. When Harry mentions that Beth is pregnant again and is confined to bed rest, Mary is sad to realize that Jed was at the Cathedral but never asked to see her. Cass asks to visit again, and Sister Tabitha assures her that she may come and pray alongside Mary.

Sister Tabitha releases Mary from her vow of silence, but Mary cannot bring herself to speak prayers in front of Cass, so she pretends that she is still under the vow. Cass comes to pray for a week, then stops coming altogether, and Harry tells Mary that Cass cannot stand seeing Travis’s pain. When he bluntly accuses Mary of being in love with Travis, she reminds Harry of his own failure to speak for her. After he apologizes and leaves, Mary clings to Travis’s semiconscious form, sobbing over her lost family and her lack of options. Travis wakes up and comforts her.

Sister Tabitha removes Mary from prayer duty in Travis’s room and gives her new studies and chores. Even so, Mary sneaks into Travis’s room every night for a week, kneeling close to him and relishing his company. One night, they hear a group approaching, so Travis pulls Mary across his body and hides her between himself and the wall, underneath the blanket. Sister Tabitha enters, checks on Travis, who is pretending to sleep, then leaves, locking them both in. Through the wall separating Travis’s room from the one next door, Mary hears someone instructing others to “keep [their] mouth shut about this” (56).

Mary carefully slips past Travis’s body to get out of the bed, tingling at the closeness of him. She tells him that it may be too risky to visit again, then jumps out the window and into the snowdrifts. Circling the Cathedral to the front, she crosses footsteps made by others and realizes that they originate from the gated path that goes into the Forest. Looking through this gate, she sees just one set of footprints and realizes that someone new has arrived and is now in the Cathedral. Mary is thrilled at the thought of an Outsider because she reasons that if someone came in, she might be able to get out.

Mary waits three days, but there is no evidence of a stranger’s presence. She tries to visit Travis, but Sister Tabitha claims that Travis is quarantined because his fever has returned. She then begins to lecture Mary, claiming that the Return occurred because people tried to cheat death and God. She declares that the Sisterhood must be an unquestioned force of authority in order to keep the village safe, and she tells Mary to stop seeking answers about things that are dangerous for everyone, including things that her mother told her stories about. She also demands that Mary forget her infatuation with Travis and focus on committing to her current position.

After Sister Tabitha leaves Mary in the hall, Mary goes into Travis’s empty room and hears a knock and a girl’s voice through the wall. The girl says that her name is Gabrielle and that she came through the gate. Mary introduces herself and explains that Gabrielle is in the Cathedral. A sudden noise in the hall sends Mary fleeing with Travis’s sheets, as if she had just collected them for the laundry. Instead, however, she makes a trip outside to peer through the window into Gabrielle’s room and sees a girl who is similar in age. Gabrielle raises a hand, then drops the curtain. Mary is thrilled with this proof of human life beyond the village.

Mary tries for many days to make contact with Gabrielle again, but she is unsuccessful. One day, Sister Tabitha sends for Mary, and Mary is shocked to see that Harry is with Sister Tabitha and has spoken for her after all. Sister Tabitha is releasing Mary from her Sisterhood vow. Mary then encounters Cass, who is coming out of Travis’s old room; Cass has come to collect Travis. Mary shows too much eagerness when asking if Travis is better, so Cass emphasizes that Travis is with her, not Mary. She tells Mary that the two of them must remain committed to their own respective partners, even though Cass admits that she is actually in love with Harry, not Travis. Mary frustratedly tries to get Cass to agree that they should speak out regarding their true emotions, but Cass refuses. Mary realizes that even if she were to reject Harry, Travis would never go against his own brother and speak for her. Although she is frustrated, she recognizes the inevitability of the current situation and agrees to Cass’s restrictions.

In the empty room next to the one where Travis stayed, Mary sees a handprint on the window glass. When she breathes on it, letters appear: Gabrielle’s name and some kind of code, XIV. She renews her search for Gabrielle but finds no sign of the girl. Though Mary will no longer become a Sister, she remains in the Cathedral because of Beth’s bedridden state.