In February, 1955, Pavel Nikolayevich Rusanov is admitted into the cancer ward of a Soviet hospital. His wife, upon examining conditions in the hospital, immediately tries to bribe one of the nurses to offer him superior care. Rusanov is a Communist Party official in charge of labor relations—a euphemism for being a government informer—and used to having privileges. He chooses this hospital rather than one in Moscow because his doctor, Lyudmila Afanasyevna Dontsova, insists that he receive treatment as quickly as possible for the large tumor on his neck. Dontsova, fifty years old and one of the older doctors, is the head of the radiology department at the hospital.

Rusanov quickly sizes up the other eight patients in the ominously named ward no. 13 and decides that they are his inferiors. He takes a particular dislike to Oleg Filimonovich Kostoglotov, a former labor camp inmate whom he nicknames Ogloyed, or “lout,” even though the man appears to be an avid reader. Dyomka, a teenage student with cancer in his leg, also reveals that he enjoys reading, now that he has the time to do so. Kostoglotov tells him that education does not necessarily make a person smarter, but Dyomka disagrees.

Kostoglotov asks Zoya, an attractive young nurse, whether he might borrow one of her medical books. His doctors never told him what is wrong with him, and he wants to know. He was near death when he arrived at the hospital less than two weeks earlier, and six months prior to that, a doctor told him that he had less than three weeks to live. Once he discovers the type of cancer he has, he asks Dontsova whether he might get a year of peace rather than undergoing the radiation treatments that will make him sick and not necessarily cure him. Dontsova becomes attached to him, in part because she is writing a professional thesis on cancers similar to his; the hospital has too many difficult cases to allow her to take a leave to finish the thesis. She recognizes the danger of radiation treatment and sympathizes with Kostoglotov.

Dyomka meets Asya, a beautiful girl, in a recreation area shared by male and female patients. She is an athlete, and she tells Dyomka that she is in the hospital for a checkup. In her opinion, she says, it would be better for him to be dead than to have his leg amputated. Dyomka receives contrary advice from Vadim Zatsyrko, another patient. Zatsyrko studies intensely in the ward and wants to go back to his research on a geological theory about radiation. He knows that he has less than a year to live, but he wants to leave behind his method of finding ore deposits.

Rusanov learns from the newspaper that the entire Supreme Court of the Union was replaced, and he has a nightmare that the people he denounced were being called to the new Supreme Court. His wife earlier revealed that amnesty was granted to Rodichev, a former neighbor whom Rusanov and his wife denounced, partly to get a larger living space.

Kostoglotov becomes friends with Vera Kornilyevna Gangart, a radiotherapist who is about his age. He is taking a diluted poison made from a mushroom that grows on birch trees, a folk cure for his cancer. She persuades him to pour out the poison. Kostoglotov finds Gangart attractive, but he also pursues Zoya. He persuaded Zoya to kiss him, and she tells him that he is getting hormone therapy that will eventually render him impotent. She briefly withholds the hormone treatments. When he stops pursuing her, she becomes...