When one of her father’s notebooks is found frozen into an iceberg, a daughter recalls the love story between her parents. A sea captain delivers the notebook to the narrator's mother at their home in northern Idaho, expressing his condolences, but her mother believes the notebook is a clue to find her missing husband rather than a sign of his death. Long ago, Thomas Hamblen, the woman's father, met Mary, her mother, as he was passing through Mary’s hometown of Sumpter, North Dakota. Mary’s father is a preacher, but she's a self-proclaimed wild woman hoping to marry a wild man. She and Thomas bond over their shared interest in disappearing. After the two fall in love and move to Idaho, Thomas leaves to explore the Arctic for months at a time. Between expeditions, he feels uneasy at home but finds solace in being reunited with Mary, who he loves dearly. Whenever he arrives home, Mary shares all she has done while he’s been away but is fairly unhappy with her domestic life. During one stretch of time at home, Thomas becomes obsessed with planning his next expedition: traveling to the Arctic by hot air balloon. He dedicates all his time to designing the balloon, writing to fellow explorers for guidance, and tinkering with supplies. Mary watches her husband swim for hours in a nearby lake and wonders if he’s losing his sanity. She begins leaving the house less. Mary soon becomes pregnant, but she doesn’t tell her husband right away, since he's in the middle of finalizing his balloon designs. One morning, she plans to tell Thomas about the baby and makes pancakes for the occasion. While cooking, she becomes excited her pregnancy might convince him to stay instead of exploring again. But before she can share the news, Thomas tells her he's going to change the world. He leaves that day, never to return. Mary later gives birth alone to a daughter, the narrator.