The novel is narrated by Kathy H., a 31-year-old carer, who takes the reader on a reflective journey through her childhood and young adulthood. Kathy was raised at Hailsham, an elite and seemingly normal English boarding school, but as she recounts her memories, subtle hints emerge that Hailsham is anything but ordinary. The students are sheltered from the outside world, closely monitored by guardians, and encouraged to create artwork that is periodically collected by a mysterious woman known as Madame. Although the students sense that they are different, they do not fully understand their fate.

At Hailsham, Kathy develops close friendships with Tommy and Ruth. Tommy is a sensitive and often misunderstood boy, frequently bullied for his lack of artistic talent. Kathy, compassionate and perceptive, forms a deep connection with Tommy, though their relationship remains unspoken. Ruth, on the other hand, is charismatic and manipulative, often controlling situations and people around her, including Tommy, whom she later claims as her boyfriend. Despite their differences, the three remain inseparable as they navigate the complexities of childhood and adolescence.

As they grow older, the dark truth about their existence begins to surface. The students of Hailsham are not ordinary children; they are clones, created for the sole purpose of donating their organs until they inevitably "complete," meaning they die. Their education and sheltered upbringing were designed to keep them healthy and obedient, ensuring that they accept their fate without resistance. However, the full weight of this revelation does not hit them all at once; it lingers beneath the surface, a reality they gradually come to understand without openly acknowledging.

After leaving Hailsham, Kathy, Tommy, and Ruth move to the Cottages, a transitional residence where former students prepare for their future as donors. Here, they experience a glimpse of the outside world but remain isolated from society. Ruth continues to assert control over Tommy, pushing Kathy aside, though an unspoken bond between Kathy and Tommy remains. At the Cottages, they hear rumors about the possibility of "deferrals"—a way for clones in love to postpone their donations if they can prove the authenticity of their feelings. This fragile hope lingers in their minds, though its legitimacy remains uncertain.

As time passes, the trio drifts apart. Kathy becomes a carer, looking after donors as they go through the stages of their inevitable fate. Ruth and Tommy begin their donation cycles, and Ruth, weakened by her condition, seeks to make amends before her completion. In a rare moment of honesty, she confesses to Kathy and Tommy that she deliberately kept them apart because she knew they truly belonged together. She urges them to seek out Madame and request a deferral. Shortly after, Ruth completes, leaving Kathy and Tommy to confront their long-suppressed feelings for each other.

With renewed hope, Kathy and Tommy visit Madame and Miss Emily, a former Hailsham guardian, to ask about the deferral rumors. Their meeting, however, shatters any illusions they had clung to. Madame and Miss Emily reveal that deferrals were nothing more than a myth, a false hope that never existed. Hailsham, they explain, was an experiment aimed at proving clones had souls, an attempt to give them some dignity in a world that viewed them as mere medical resources. But the experiment failed, and society continued to turn a blind eye to the ethics of cloning.

Heartbroken, Kathy and Tommy are left to accept their fate. Tommy, having already begun his donations, eventually reaches completion, leaving Kathy alone with the weight of her memories. She knows her time as a carer will soon end, and she, too, will begin the donation process. Yet, as she stands before an empty field, she allows herself a moment of reflection, grieving not just for Tommy and Ruth, but for all the lives lost to a predetermined fate they never had the power to change.

Through its melancholic yet deeply human narrative, Never Let Me Go raises profound ethical questions about the cost of scientific progress, the nature of free will, and the fundamental desire for love and connection. Kazuo Ishiguro crafts a masterful story that lingers in the mind, reminding readers of the fragility of life and the importance of the memories we leave behind.