Dr. Pascal is a sixty-year-old scientist, a pioneering doctor, and medical works come out of his pen. He practices medicine using his own methods and giving hope to the sick. He is interested in questions of heredity. Using the example of his own family, he creates his own theory of heredity based on the data of the genealogical tree compiled by him. Pascal's mother, Felicite, is an eighty-year-old woman enjoying her position and status in society, protecting family secrets that could blacken the glory of the Rugon. In 1851, the Rogons saved Plassan from anarchy, contributing to the recognition of the coup. Felicite sought to destroy the works of her son, who exposed in a bad light the heredity of their family.
Pascal lives away from civilization, in a house with Martina, a faithful servant in love with him, and her niece, twenty-six-year-old Clotilde. Clotilde’s brother, Maxim, fifteen years ago at the age of seventeen became the father of the child whom the maid gave birth and who was destined to become a victim of degeneration of the clan. Charles was mentally retarded, as was his great-grandmother, Adelaide Fook, who had been in the Tulet’s mental home for twenty years. Charles was handsome and graceful, but the imprint of imminent death was read on his face - a consequence of degeneration. Once Pascal, Clotilde, Felicite and Maxim went to the old eighty-three-year-old uncle Makkar, an old drunkard, who seemed "canned in alcohol." In the past he was a gangster, and Felicite had long dreamed of getting rid of this vicious relative. Then the family goes to their ancestor, Adelaide Fook, an old woman, a “forgotten death” who was one hundred and four years old, she was indifferent and only looked indifferently at everything around. Before the eyes of Pascal, the whole century was resurrected: Adelaide, Makar, Felicite, he himself, Clotilde, Maxim, Charles.
Pascal falls ill with an unknown disease, he languishes, leading an ascetic lifestyle, he is used to suppress his passions, and now he dreams of a lover who gives him unearthly bliss. After some time, he realizes that he has a passion for Clotilde, she reciprocates. Blinded by passion, the doctor spends his last money on generous gifts for his beloved, who actually ruin him, while the notary, hiding, upsets his condition.
Felicite, who once went to Makkar, found him sleeping with a pipe in her lap, she tried to wake him, but in vain, the old robber was in a drunken stupor, she did not interfere with his burning, which turned him into a handful of ashes. Clotilde and Pascal, who came to Tulet the next day, witnessed the faded life of a boy who had bled to death in front of his ancestor Adelaide. In the house of the old robber, Clotilde and Pascal saw only a handful of ash and a glove dropped the day before Felicite.
Meanwhile, Pascal’s affairs were completely upset; he was forced to ask for money from clients who had previously owed him money. Clotilde sold almost everything presented to her by Pascal, leaving only a chain with pearls.
Maxim, Clotilde’s brother, started having a dry spinal cord, he was confined to a chair and asked his sister to come to take care of him. Felicite, who did not approve of the connection between her son and granddaughter, advocated that Clotilde soon leave, breaking the connection with Pascal, or that they register a marriage. Pascal was worried about his age, he did not want to spoil the life of Clotilde with his old age. He wanted to see her as a mother and so that she could find her happiness with other people, because he felt that his heart disease was undermining his strength.
Clotilde leaves and two months later in a letter informs Pascal about her pregnancy. Pascal is insanely happy and at the same time doomed to a quick death, he wants to extend his life for at least a year to see his child. He sends a telegram to Clotilde so that she will come soon. Clotilde hurriedly packed up and left, but did not have time to catch Pascal alive, he had an attack, and Dr. Ramon, his closest friend, could not extend his existence. At night, Felicite, taking advantage of the reigning silence in the house, burns all the works of a scientist who kept the secrets of their heredity and could overshadow the glory of the family. Clotilde can only save the family tree, on which, before his death, Pascal left the last mark on his own death and the approximate date of birth of his son. The ambitious Felicite after some time created a shelter for the elderly named Rugon, and Clotilde, to whom Pascal's condition returned, gave birth to a son, continuing to live in their house.
