The following version of this book was used to create the guide: Three Days in June. Alfred A. Knopf, 2025. Kindle Version.

Protagonist, Gail Simmons, is at Ashton School when the novel opens. She is the Assistant Headmistress when she learns that Marilee, the headmistress, must have a heart procedure performed. Marilee is not too concerned because she has previously had this procedure. She tells Gail that she will likely leave her job before the next school year because she wants to start traveling with her husband. Gail has always assumed that since she has been the Assistant Headmistress for years that she will become the new headmistress. Instead, Marilee has determined that Gail does not have the people skills to be headmistress. So, Marilee has found someone else she would like to hire. The new woman wants to bring her own assistant. This would leave Gail without a position in the administration. Gail walks out of the school, hurt and angry.

Gail goes home to find that her ex-husband, Max, is there. Max is in town for their daughter Debbie's wedding. Max has a cat with him that he is fostering. He was planning to stay at Debbie’s house both tonight and the night of her wedding. However, he learns that he cannot stay there because Kenneth, Debbie’s fiance, is allergic to cats. Since he knows where Gail keeps a spare key to her house, he goes there to stay. He thinks Gail should adopt the cat. This is not altogether dissimilar to how Max and Gail met because Max moved into a house she shared with other ladies and brought a dog without warning anybody.

Max thinks Gail is a good teacher and should go back to teaching. The two learn from Debbie that she has been told that Kenneth recently cheated on her. Debbie wants to call the wedding off, and Gail fully supports cancelling the wedding. Max convinces his daughter to speak with Kenneth. After speaking to Kenneth, Debbie tells her parents that it was all a misunderstanding and that the wedding will go as planned. Everyone knows that Kenneth really did cheat. However, Debbie, believing that marriage does not have to be permanent if she does not want it to be, decides to marry him anyway.

Debbie calls her parents the morning of the wedding, and they go suit shopping for Max at Debbie’s behest. Max does not want a new suit, but he does want to make his daughter happy. At the suit store, Max starts to endear himself to Gail. He does this when he looks proud wearing a suit that makes him look like a funeral director. Gail realizes that he is willing to do what is necessary to make Debbie happy. This continues in the car as he talks to Debbie about the World Series, a topic that does not interest him in the least.

Debbie does not want a wedding planner or a large wedding, but her future mother-in-law, Sophie, acts as a wedding planner regardless. Sophie exerts her will numerous times, allowing the wedding to get more elaborate than Debbie wants. Despite this, the wedding still does not live up to what Sophie wanted it to be. The wedding proceeds smoothly, and the families go to the reception. There is some tension because Kenneth is angry at his sister, Elizabeth, for telling Debbie about his affair. In the end, however, she gives a toast to her brother. When they return home, Gail is happy to have Max to rehash the day with.

Since Max does not leave early on Sunday morning, he and Gail spend much of the day together. Gail’s narration reveals that while married to Max she had an affair with Andrew, a co-worker at another school where she had taught. Before learning of Gail's affair from Gail's unsent email on the computer screen, Max had always idolized and pursued her. After she admitted to the affair, he no longer looked at her in the same way. She could not handle being imperfect in his eyes. So, she decided to leave him. Max spends the day after Debbie’s wedding trying to get Gail to move near him and take a job at his school. Finally, she relents to his desire for her to adopt the cat he brought. Max leaves, but he comes back to propose that he will adopt the cat. It can be a joint cat if she comes to live near them. Gail takes Max’s face in her hands and kisses him.