The following version of this book was used to create the guide: Hall Kelly, Martha. Lost Roses. Ballantine Books, 2019.

Lost Roses is divided into a prologue, 54 short chapters, and an epilogue. The plot outlines the lead up to the Russian Revolution and its aftermath, conveyed through the first-person perspectives of four young women. Kelly takes readers from the United States to across the sea in Russia and France, conveying the destruction of the Imperial Romanov dynasty from the perspectives of the Russian aristocracy, the destitute Russian peasantry, and the influential, affluent Woosley family in early 19th century America.

The novel begins with the narrative of Luba in 1912, belonging to the Streshnayva family related to the Russian tsar. Luba recalls having been resentful of her sister Sofya's developing friendship with Eliza after the death of their mother. The women take her to the Paris Planetarium, where Sofya tells her that their mother Agrafena is in the stars. It occurs to Luba that she should be grateful for Eliza, who has become a second sister to her.

In 1914, Eliza Woolsey Mitchell attends a party at her mother's seaside manor in Southampton. Sofya gives birth to her son Max, and the Streshnayvas and Eliza leave for St. Petersburg shortly after. Eliza notes the rising civil unrest in the Russian city, while Sofya, her father, and stepmother downplay the riots and rising violence. After a party at Anichov Palace ends with a former imperial guard turned rebel's attempted assassination of the tsarina, Eliza is attacked by a bandit on the tram and is minimally wounded. Two years later, Sofya and her family seek the safety of their estate in Malinov, as circumstances become more dangerous for the Russian elite.

Varinka Pushinsky's perspective is introduced, establishing that the Russian peasantry is in famine. Varinka's mother, referred to as Mamka, does a tarot card reading for Sofya's stepmother Agnessa. The cards indicate that a boy was born into Agnessa's family two years before, in reference to Sofya's son Max. Mamka predicts that the boy will be taken from his mother, and among other cards drawn, a scythe indicates impending death. Eliza and her husband Henry purchase a historic country home in Connecticut and name it The Hay. Soon after, Henry dies of pneumonia and Eliza is devastated by his sudden death.

In Malinov, Varinka secures a position as nanny for Max at the estate and develops love for him, fantasizing that she is his mother. Varinka reveals that she has been sexually abused by Taras beginning in childhood, a hunter and ex-con who supports herself and Mamka in exchange for sexual acts. Taras informs her of the impending revolution, and how the rebels are planning a revolt against the Russian aristocracy, including the Streshnayvas. Sofya and her family make preparations to leave Malinov and flee to Paris, and shortly before the family leaves, the rebels break into the estate. The Streshnayvas are confined to the barn on the estate and are faced with an uncertain fate.

In New York City, Eliza grieves for her husband and enters a period of mourning. When she no longer receives letters from Sofya, Eliza pursues obtaining visas for the Streshnayvas, to no avail. Eliza's mother advises her to channel her sadness into philanthropy, and she is inspired to establish the The American Central Committee for Russian Relief. Eliza finds meaning and solace in her assistance of the Russian refugees, arranging housing and work for the women.

The Streshnayvas spend the winter of 1917 in captivity. Max is spared from imprisonment, in the care of Varinka. Sofya narrowly escapes the rebels and journeys to Alexander Palace on horseback, hoping for the royal family to send an Imperial guard to Malinov. Sofya learns that the tsarina and her children have been confined to the palace and she must escape or face imprisonment. Sofya returns to Malinov and finds her family burned and impaled on the gates of the estate. Varinka refuses to relinquish Max and Sofya is forced to leave without him.

Varinka, Max, Mamka, and Taras reach Paris in 1919. Varinka is determined to be a mother to Max and he is enrolled at L’Ecole Cygne Royal. Sofya arrives in Paris shortly after with little money. She stays in a boarding house occupied with Russian women whom are also displaced members of the aristocracy. Meanwhile, Eliza arrives in Paris to search for Sofya. Varinka is determined for Max to believe she is his mother, despite indications that he remembers Sofya and yearns for her. Sofya awakens in the boarding house to the sound of her sister's voice, revealing that Luba survived the execution on the Malinov estate. Sofya stands guard on Taras' townhouse while Luba breaks into the house to obtain Max's school enrollment letter. The sisters take the letter to the headmistress of Max's school. Madame Fournier rejects Sofya's insistence that she is Max's biological mother, and fearing Taras' vengeance, the headmistress forces them to leave the school.

Eliza searches for Sofya on Rue Daru, where many Russian émigrés are known to frequent. She visits a doll factory occupied by Russian women and children hidden in the Saint Alexandre Nevsky Cathedral. The refugees must work in secret to avoid detection by the Red Army, a Bolshevik group that seeks to eradicate the Russian nobility that fled to Paris. Eliza is informed of a charitable Russian aristocratic woman who is helping to feed the workers. Believing the woman is Sofya, she is directed to the Russian restaurant across the street and is reunited with her friend. In a confrontation with a violent Taras, Varinka reveals that he is her half-brother, deeming their sexual interactions incestuous. Herself, Mamka, and Max escape the townhouse after Varinka handcuffs him to a bed.

Sofya, Eliza, and Luba return to L’Ecole Cygne Royal with protection secured by a former general of the Russian imperial army. Varinka joins them in the headmistresses' office with a suitcase, aiming to leave for Russia with Max. After Max's hesitation and Sofya's encouragement, the boy recognizes his mother and approaches her. Varinka confesses to having taken Max and Sofya issues an ultimatum: either she presses charges for child abduction, or Varinka leaves the city. Varinka departs Paris for Russia and Max is returned to Sofya's custody.

The Epilogue features Luba's perspective in 1920. Herself, Sofya, Max, and Eliza had remained in Paris while the Streshnayvas' visas were secured. The family moves into Eliza's mother's house in Southampton. Luba, Sofya, and Max change their names, due to the enduring Bolshevik threat and rising communist sentiment in America. Luba continues to grieve her past life and the deaths of her family members. As the novel ends, Luba is determined to be optimistic of her new life in the United States.