On a spring morning in 1965, a Dublin resident, journalist Younger, who is sixty-five years old that day, receives a strange message. Its authors. Celestials from Olympus, who are in Eternity, inform him that they have chosen him as the “experimental participant in the experiment,” which provides him with the opportunity to live his life anew. The celestials opted for Yanger because he is a "minor face" and therefore will not cause them any trouble. Younger is hinted that if he refuses to participate in the experiment, then in an hour he will die under the wheels of a truck. At the same time, the Celestials indicate to him that they, as supernatural beings, foresee his decision and congratulate him in advance. At the same time, they put two conditions for his “second coming” to Yanger: without losing the fullness of his life experience, he will forget almost everything that he has experienced, and the sixty-five years granted to him will live in the reverse order, steadily growing younger, while he is “at mature zero age” will not drag back the "maternal womb of Time." Younger goes outside to "check" if he really faces the death predicted by the Celestials. When he sees a truck that is about to crush a little girl, for several painful seconds he does not know what to do: get the girl out from under the wheels and die himself or watch her death indifferently. But unexpectedly for himself, he feels a fear that completely paralyzes his will, and he sees with horror how the truck driver and the girl die. He is indignant at the insidiousness of the Celestials, who deftly played on his cowardice and actually deprived him of the choice. Yanger believes that "a person is unable to decide freely if he does not know what kind of person he is." However, in anticipation of a new life, Younger quickly consoles himself and is trying, at least in basic terms, to restore his former life.

Part 1 Ana. 1965–1970

His old lover Ana French (she, like him, turns sixty-five this day), to whom he explains that he suffers from amnesia, helps him remember everything related to their long-standing romance. Ana tells him the extremely complicated story of their relationship, about how the “love triangle” took shape, in the occurrence of which her husband, gynecologist, avid athlete, careerist and, incidentally, impotent, played an important role. Five years pass. Younger gradually gets a taste of the “second” life that was given to him and, continuing to love Ana, is fond of her daughter, the artist Anadion, whose husband, sculptor Leslie Longfield, was also Ana's lover. Ana dies, and Yanger sums up the five years of his life, lived in the “reverse order”: he realized that every choice means “unconcerned submission to fate,” and wants to relive everything anew. On shares with Leslie Longfield, Younger opens a small art gallery that serves as a convenient screen for him to communicate with Anadione.

Part 2. Anadione. 1970-1990

Younger meets with Catholic priest Des Moran, whom he knew many years ago. He recognizes Yanger and confesses to him that when he was still a young student-theologian, he had a love affair with Ana and he was sure that Anadion was his daughter. Younger discovers that Leslie met an elderly man named Jimmy Younger at an exhibition of his works in Philadelphia, who considers himself the son of a well-known journalist, Robert Younger. Younger, who continues to grow inexorably young, is amazed that he has a son who is already fit for his fathers. In addition, it turns out that Jimmy, who was a boy in America, was taken care of by Yanger's brother, Stephen, whom he also remembers nothing. Moreover, Younger discovers that Jimmy has a son named Bob in his honor. Younger is increasingly entangled in the maze of his past. Anadione is fifty-four years old, and her daughter Nana is seventeen. Younger flirts with a girl, aging Anadione suffers from jealousy. Leslie dies in a ridiculous accident. Younger becomes Nana's lover, and Anadion soon dies. Younger finds out that before his death, Leslie, who had guessed about Yanger's connection with Nana and intercepted their love messages, gave all the letters of Yanger to Nana and Anadion Des, and he showed them to Nana. This leads to a quarrel between Nana and Yanger. At that moment, Bob’s grandson, who came from America, came to the house to find all the Youngers he could find, because he was deeply concerned about the past of his heroic family, distinguished himself in the Irish uprising.

Part 3. Nana. 1990–2024

In a conversation with Bob, who stubbornly asks him for information about his grandfather’s brother, Younger has to impersonate his own father and become his own son. Bob and Nanu are attracted to each other, Nana becomes his secretary, studies family archives and gets acquainted with the genealogy expert Amy Poinset. Nana concludes that Yanger's physical existence cannot be confirmed by any documents. She tells Yanger that Bob actually came to find out if there were any relatives left in Ireland who could claim a large inheritance: the fact is that Bob's father died without a will. Realizing that Yanger is hiding something from her and does not want to open up to her, she leaves for Paris to study philosophy, but Yanger comes there and reveals her secret to her. They become husband and wife and in 1994 they have a daughter, Ana. The girl is sent to study in a boarding school, and Nana, at forty-one, receives a Ph.D., but she becomes painfully sensitive to the difference in their years. When Younger is so young that he looks younger than his daughter, Nana persuades him to leave.

Part 4. Christabel. 2010–2015

Younger meets Bob Younger in Boston, introduces himself as his own son, and visits his estate in Texas. He falls in love with Bob's sixteen-year-old daughter, who was named Christabel after her great-grandmother, that is, Yanger's first wife. He becomes her first lover, but the romantic disposition of his soul is alien to her, and she soon abandons him to marry a Jew Bill Meister, who is twice her age, although Father Christabel is terrified of such an alliance. Amy Poinset comes to Bob's estate and exposes Yanger, who, according to her, is an impostor and a deceiver. A family scandal is played out, and Kristabel, having shot his father with a revolver, wounds him, after which he flees with Yanger. After some time, Younger learns that Christabel obeyed her father’s will and abandoned her marriage to Bill Meister. Younger, who will soon be thirteen years old, misses Nana and two years later begs her in a letter to let her return.

Part 5 Farewell. 2030

Nana leaves the university, where she lectured on philosophy, does not see anyone and devotes her life entirely to Yanger. Now she herself writes in his notebook, noting the age-related metamorphoses of her husband, who is turning into a lovely baby. Once a one-year-old baby Yanger, who manages to crawl to his notebook, leaves a farewell note in it. If before, at the very beginning of his “second life”, he only suspected that it was impossible to live a whole life again, now he is sure of it. However, Yanger is grateful to the gods for this gift, and Nana - for her love, thanks to which he, Yanger, in his beloved recognized the features of his mother, for seeing in Nana's appearance “the outcome of his life, the combination of ends and began.” Younger thanks Nana for revealing his past to him and going to lose with him. The last entry in the notebook was made by Nana's hand. She writes about how Younger shrunk to the size of a silkworm, and then disappeared. She is puzzled by the question, for what purpose did the gods conduct this experiment, if it was obvious to them that no matter how much you add life experience to a person, he still will not learn anything. Nana has the feeling that the gods simply forgot about the purpose of their cruel game, and she does not exclude the possibility that she will be offered to get younger, and Yanger, who is somewhere nearby, tiny, like a moth, will grow and grow up again. Thinking about this opportunity, she realizes that she will gladly agree to everything, just to be with him, with a boy, an adult, an old man. "Again and again and again and ..."