Both Cal and Margaret regret their actions and vow not to repeat the mistake. Still, they are drawn to each other. They begin meeting each Thursday at Margaret’s house to have sex. Felix’s letters make Margaret feel pangs of guilt, but she tries to ignore them. After so many years of loneliness and feeling unwanted, Margaret cannot give up her meetings with Cal.

On his ship, Felix is enjoying military life. His work is not unlike the job he left behind in Bonhomie, although he can’t adjust to how loud and hot the ship is. While smoking with the other guys, he meets a soldier named Augie, and a look passes between the two that fills Felix with excitement.

They continue to talk and exchange what seem to be meaningful glances, and one day, while on R&R on an island, they have sex. Afterward, Felix is filled with longing even though he knows that nothing can come of their relationship. Augie plans to return home, settle down, and start a family, and Felix is married. Felix begins to ignore Augie, even though it pains him to do so. Suddenly, tragedy strikes: The ship is torpedoed, and everybody has to jump off. Not everyone makes it. 

Margaret receives a telegram: Felix has been reported missing in action. She is filled with terror and shame. She cannot believe that she cheated on Felix with Cal. She doesn’t want to be a widow and has no idea how to pay their mortgage or live a “normal” life. She tells no one about the telegram and cancels plans with Cal.

Margaret waits for a phone call or another letter, and one day, Felix himself calls. He broke ribs, his collarbone, and his shoulder. He is going to be sent first to a specialist in San Francisco, California, and then home. Margaret is flooded with gratitude. She buys all of Felix’s favorite foods and has his clothing cleaned and pressed.

Cal has been dealing with problems of his own, but he wonders about Margaret’s sudden change of heart. His father Everett’s drinking has gotten worse, and he is going to stay with Becky and Cal at their home for a few days. He takes Everett to the hardware store and runs into Margaret. She invites him to the dance club, where she tells him about Felix. The two share one last dance together, aware that their affair is over.

The narrative returns to the explosion on Felix’s ship. Felix is in the water, fighting for his life. One of his arms is not working, and he is tangled in some kind of netting. He breaks free and begins to swim. One of the other wounded soldiers, out of his mind with pain and in shock, grabs onto Felix. They both go under before Felix fights him off and makes his way to a small life raft. Looking back, he sees the man floating face down. He looks around for Augie but does not see him.

Felix is sent to a hospital in Manila in the Philippines, where, on morphine because of his injuries, he repeatedly asks about Augie and tells his doctors that he wishes he’d gone down with the ship. The doctors send him to a psychologist in San Francisco, to whom he must prove his mental wellness before being sent home. He does so and begins the long train journey to Bonhomie. At home, he and Margaret are nervous around each other at first. Both are grateful that they successfully have sex on his first night back.

When the war ends, Becky feels both gratitude and uncertainty. The bombs that the US dropped on Japan killed hundreds of thousands of civilians, and she isn’t sure how she feels about that. She also wonders what life will be like for the families who lost loved ones and for the returning soldiers trying to resume their old lives.

She and Cal are still distant, and even when he finally moves back into their bedroom, she senses tension. She also thinks that he appears remorseful, and she decides that remorse is a sign of his good character. Underneath it all, Becky still loves Cal and hopes that he accepts her spiritualism someday.

Margaret is one of the many women who become pregnant shortly after the war’s end. Everyone around her is thrilled, but Margaret is not. While other women characterize the feeling of a baby moving in their womb as “butterfly” flutters, Margaret thinks that it feels more like snakes. She asks her doctor if it is possible for a mother to be allergic to her fetus, and he seems alarmed. Margaret now understands her own mother because she also does not want the child she is carrying. To make matters worse, Felix returned from the war haunted by something that he won’t discuss.

Margaret gives birth to a boy, Thomas Aquinas, or “Tom,” and Felix is overjoyed, but Margaret is not. Breastfeeding is so painful that she switches to formula almost immediately, but she finds the routine of preparing bottles exhausting. Felix clearly loves Tom more than Margaret does, and she resents the fact that mothers cannot abandon their children.

One day, she runs into Cal. He asks how old Tom is, and when she replies that he is seven months old, she hastily adds that she got pregnant right after Felix returned. She is not actually sure who Tom’s father is, but she doesn’t want to ruin two marriages, so she plans to never reveal her infidelity to anyone.