The film tells about L.A. Durnov - Academician of the Russian Academy of Sciences, Corresponding Member of RAMI, Director of the Research Institute of Pediatric Oncology and Hematology. The following filming was used in the film: L.A. Durnov's book "Notes of a Children's Oncologist"; a panorama of the building of the Research Institute of Pediatric Oncology and Hematology, along the corridor inside the building; a boy looks out of a hospital window, a woman with a child at the window; L.A. Durnov talks about pediatric oncology, about how sometimes doctors are late with a diagnosis (sinhr.); L.A. Durnov is sitting in his office; L.A. Durnov with a group of doctors during the morning round, doctors are examining a picture of one of the sick children, children with a nurse in the hospital corridor, doctors headed by L.A. Durnov enter the ward where Petya Fetisenkov lies, talk with Petya in incl. and L.A. Durnov (sinhr.); Petya Fetisenkov during the irradiation procedure; doctors are carrying a sick child on a gurney; a kitchen worker drives a lunch trolley down the hallway, children watch TV, compete in the hallway in wheelchairs, girls play with dolls in the ward; a nurse gives one of the girls an IV drip; L.A. Durnov prepares for the operation, conducts the operation; mothers with sick children are in the ward, one of the mothers is sitting by the bed of her daughter, who is given an IV; internal view of the hospital chapel, a mother with her daughter in her arms in the chapel, lighting a candle at one of the icons, parents with children at the service in the hospital chapel, priests giving communion to children; parents of a sick boy - Petya Fetisenkova are sitting at the table, Petya's mother calls L.A. Durnov on the phone, doctor L.A. Durnov talks with Petya's mother (sinhr.); Petya Fetisenkov with his parents and other children goes to school on September 1, schoolchildren with their parents stand in the school yard during a rally.