Eighty-year-old Noah Calhoun, who lives in a nursing home in North Carolina, describes the lonely and sometimes painful nature of his final days. Noah knows that he has lived an ordinary life by most people’s standards, but he insists that having known “perfect love” has been enough for him. Noah wanders down the cold halls of the nursing home to visit the room of another patient—a woman—who barely acknowledges him as he sits down beside her, opens up a small notebook, and begins to read to her. Noah is hopeful that today will be the day a miracle happens.
The story flashes back to October of 1946. As dusk falls, Noah sits on the porch of his sprawling home in New Bern, North Carolina. Noah is proud of the work he’s done on the old plantation house—a few weeks ago, a reporter even came to interview him about it and take pictures. Noah is a simple man who spends his days kayaking, reading poetry, and playing guitar with his neighbor Gus. But all the while, Noah pines for a lost love: in 1932, he shared an intense, romantic summer with a young woman named Allie Nelson whose family came to visit New Bern for several months. At the end of the summer, after losing their virginities to each other, Noah and Allie parted ways. Though Noah wrote Allie many letters, she never answered them, and he has not heard from her or seen her since.
The following morning, Allie arrives in New Bern from Raleigh to visit Noah—and to tell him about her engagement to the wealthy lawyer Lon Hammond, Jr. Allie has recently read a newspaper article about Noah’s renovated house and, in the weeks since, has been unable to think of anything else—even though her wedding to Lon is just weeks away. Allie has come to New Bern under the guise of going antiquing. As Allie bathes, dresses, and gathers her courage to head out to visit Noah, the narrative switches back to Noah’s point of view as he reflects on the years since Allie’s departure from New Bern. After heading up north in search of work at the height of the Great Depression, Noah found a job at a scrap yard owned by the kindly Morris Goldman, a man who took a shine to Noah. When Noah returned from fighting in World War II, he found that Morris had left him a significant portion of the company. Noah bought the plantation house and the surrounding land with the funds, and in the 11 months since, he’s dedicated himself day and night to fixing up the property. Lost in thought, Noah finishes his daily tasks, showers, and sits out on the porch. He is surprised when he spots a car coming down the drive—and he is even more shocked when Allie steps out of it.
After standing and staring at each other, Allie and Noah embrace excitedly. Allie tells Noah about having found the article and compliments him on his beautiful handiwork. She apologizes for showing up out of the blue, but Noah assures her that he’s excited to see her. Allie tells Noah about her engagement, and the two of them take a walk down to the river. As Allie tells Noah about Lon, he senses hesitation in her voice. Noah invites Allie to stay for dinner, and she accepts. Allie and Noah continue reminiscing about their summer together as they prepare dinner and tour the house. When Noah asks Allie why she never answered his letters, she becomes confused—she says she never got any letters. Soon, Allie realizes that her mother, Anne, who disapproved of Noah for being of a lower social class, must have confiscated the letters. Noah asks Allie if she thinks they’d still be together if she had gotten the letters, and she admits that she thinks they would be.
Noah then asks Allie about Lon and about her passion for painting, Allie admits that she gave art up despite going to college for it. Noah takes Allie to the living room and shows her that he has hung a painting she gave him long ago over the fireplace—he assures her that she is a true artist and should give painting another shot. Over dinner, Allie realizes that she and Lon never talk as freely as she’s conversing with Noah. After dinner, as Noah reads Allie poetry on the porch, Allie feels a sensual stirring inside of her and thinks that she doesn’t feel this kind of passion for Lon. Overwhelmed, Allie leaves in a hurry. As Noah walks her to her car, he invites her back the following day. Allie accepts his invitation and returns to the inn, unaware that Lon has been trying to call her room all night long.
The next day, as Allie and Noah enjoy their separate mornings, they find themselves lost in thoughts of each other. Noah kayaks as he does every morning, while Allie heads to a department store to purchase some art supplies and make a couple of quick sketches. At noon, Allie drives out to Noah’s, where Noah tells her he is taking her for a surprise. Allie follows Noah down to the river and hops into his canoe. The two set off down the river, again reminiscing about their summer of love as they paddle downstream. When Noah turns off into a small lake, he tells Allie to close her eyes. When she opens them again, she finds that Noah has led them to a secluded cove—they are surrounded by hundreds of swans. After feeding the birds, Allie and Noah notice thunder and lightning approaching. They begin rowing home, but they get trapped in the storm anyway. Allie laughs rapturously as she and Noah are soaked to the bone. Back at the house, Allie and Noah sit in front of the fireplace and sip bourbon as they continue reminiscing about the summer of 1932. When Allie asks Noah if he recalls having sex at the end of the summer, neither of them can resist their feelings any longer. Overcome by passion, the two have sex by the fire. Meanwhile, back in Raleigh, Lon asks for an adjournment in the case he’s working on. He tells the judge he has urgent business to attend to over the weekend, and the judge urges him to be back by Monday at nine. Lon accepts the judge’s mandate and hurries to his car to begin the drive to New Bern.
The next morning, Allie and Noah are in the kitchen when there is a knock at the door. Noah goes to answer it—and he’s shocked to find himself face to face with Allie’s mother, Anne Nelson. Noah welcomes Anne in, and he and Allie sit with her in the living room. Anne tells Allie that she’s noticed her behavior was strange for weeks—and she knew it had to be due to the article about Noah. Anne warns Allie that Lon is on the way—he called the house last night deeply upset, having figured out what Allie was doing in New Bern. Before leaving, Anne gives Allie the letters from Noah and urges her to “follow [her] heart” as she chooses what path her life will take. After Anne leaves, Noah asks Allie what she wants to do. She tells him she is afraid of hurting or upsetting anyone. Noah, however, insists that Allie must do what she wants to do—she must live a life which doesn’t constantly force her to keep looking back and wondering what could have been. Allie begins crying, and Noah tells Allie he already knows she won’t stay. He walks her to her car and helps her inside. He tells her he loves her before she starts the engine, but Allie stoically begins driving away without looking back. Allie continues crying all the way to the inn. When she arrives, she spots Lon’s car in the parking lot. She turns off the engine and reads Noah’s final letter to her, from March of 1935, as she puzzles over what to say to Lon. By the time Allie is finished reading Noah’s last note, she knows exactly what to say, and she heads into the inn with purpose.
The narrative returns to the frame story in the future. Noah finishes reading the notebook and closes it. His female companion—whom readers can now infer is Allie—is comforted by the story and asks if Noah wrote it himself. Noah says that while he didn’t write it, it is a true story. Allie tells Noah that she has a question for him but doesn’t want to hurt his feelings—she asks him, confusedly, who he is. Noah becomes lost in thought as he reflects on the full, beautiful life he and Allie made together. They have four children and many grandchildren, and Allie is a world-famous painter—yet most days, her Alzheimer’s disease prevents her from remembering any of this. Nevertheless, Noah reads to Allie each day in hopes of jogging her memory and enjoying just a few lucid moments with her. Noah spends much of his free time reading old letters and looking at old photographs, reminiscing about the past.
One day, Noah invites Allie on a walk, and she accepts. Together, as they walk the grounds of the nursing home, Allie continues asking questions about the story and inquiring about Noah’s own life. Allie tells Noah that she believes she has a secret admirer—she tells him she often finds notes and poems tucked into her coat pockets or under her pillow. Noah chuckles and leads Allie back up to her room, where the nurses have set out a candlelight dinner for the two of them. The nurses are charmed by Noah’s devotion to Allie and help him woo her every chance they get. As Allie and Noah sit down to dinner and listen to music playing on the stereo, Allie recognizes Noah and tells him she’s always loved him. The two of them enjoy a couple of blissful hours together eating and talking—but soon, Allie begins fading away again. She is suddenly unable to recognize Noah and begins screaming for the nurses, who come down the hall to sedate her and remove Noah from her room.
Noah endures several lonely, foggy days without Allie. One morning, while looking through old letters again, he experiences pain, numbness, and loss of vision—he knows he is having a stroke. After two weeks of being intubated and moving in and out of consciousness, Noah is finally cleared to return to the nursing home. On his first night back, he spends hours losing himself in old letters, photos, and memories before shuffling down the hall toward Allie’s room, having missed her terribly. Though Noah is not supposed to visit Allie after dark, the night nurse, Janice, lets Noah pass. She tells him how much she admires him and how inspired she is by his and Allie’s enduring love. In Allie’s room, Noah sits at the edge of the bed and slips a poem beneath her pillow as she sleeps. He cannot stop himself from caressing her face. Allie wakes and turns to face him. Noah is afraid she won’t recognize him and will begin screaming—but instead, she smiles and addresses him by name, tells him how deeply she’s missed him, and begins undoing the buttons of his shirt.