Never Let Me Go follows Kathy H., who reflects on her childhood at Hailsham, an isolated boarding school where she grew up with her closest friends, Tommy and Ruth. Although their lives initially appear ordinary, the students gradually discover a devastating truth: they are human clones created solely to donate their organs to others.

As they grow older and leave Hailsham, Kathy, Tommy, and Ruth struggle with friendship, love, jealousy, and the realization that their futures have already been determined. Hoping to escape their fate, Kathy and Tommy investigate a rumor that couples truly in love can postpone their organ donations. However, they learn that no such possibility exists. Hailsham's real purpose had been to prove that clones possessed souls, emotions, and humanity through their artwork, but society ultimately chose to ignore that truth.

After Ruth's death, Kathy and Tommy finally begin a relationship, but their happiness is brief. Tommy starts donating his organs and eventually dies, leaving Kathy to face her own future as a donor. Rather than resisting through violence, Kathy preserves her identity by remembering the people she loved and the life they shared.

The novel explores themes of humanity, mortality, memory, love, friendship, and the ethics of scientific progress. Through its quiet and deeply emotional narrative, Kazuo Ishiguro asks what truly defines a human life and reminds readers that dignity, compassion, and meaningful relationships give life its greatest value, no matter how limited our time may be.