The novel alternates between two timelines. In 1996 Paris, Emma Hart, a 24-year-old American art student, cleans apartments to survive after her scholarship at the École des Beaux-Arts was abruptly canceled. In 1891 Paris, Claire Donadieu, a young prostitute, enters the life of Jo van Gogh, the recently widowed sister-in-law of Vincent van Gogh. The stories converge through a hidden Van Gogh Sunflowers painting and the powerful Swanson art-dealing dynasty.
A prologue opens with an unnamed narrator trapped in a climate-controlled chamber with bulletproof glass and stone walls, convinced they will die there. The narrator's identity remains hidden until later.
Emma's employer is Stella Swanson, the elderly widow of Maxwell Swanson, patriarch of Swanson Enterprises, the world's largest art dealership. Stella lives alone in a Parisian penthouse where faded rectangles on the walls mark where paintings once hung, stripped away by her stepson Louis. Emma meets Matthew Swanson, Stella's step-grandson, who has been tasked by Louis with convincing Stella to enter a care facility, though Matthew privately resists. Emma lives with two roommates: Colette, a forensic art analyst, and Lucie, a bold Turkish expat who supplements their income through sex work. Emma is haunted by her past with Pascal, a predatory art professor who seduced and discarded her, and by guilt over leaving her mother, who has a mental health condition, in a Philadelphia care facility.
In 1891, Claire saves Jo from a violent attacker on the streets of Montmartre. Jo's late husband, Theo, was Claire's client and confidant; before dying of syphilis-related dementia, he begged Claire to watch over Jo. Claire enters Jo's cramped flat, filled floor to ceiling with hundreds of unsold Vincent van Gogh paintings. Jo is destitute and threatens to burn the canvases for heat.
Emma grows closer to Stella, who reveals a hidden dressing room with a concealed panel. Behind it hangs a previously unknown Van Gogh Sunflowers painting. Stella explains that her grandmother Claire befriended Jo in the 1890s; Jo gave Claire several of Vincent's paintings when they were considered worthless, and Claire passed the last one to Stella as an insurance policy. Emma discovers that Stella was the anonymous donor behind the scholarships for all three women, recruiting them as allies in case she was cut out of the Swanson fortune.
Jo asks Claire to move with her to Bussum, Holland, to run a boardinghouse while Jo tries to sell Vincent's work. Claire agrees, leaving behind her daughter Marie-Celeste, whom she gave up as an infant. Jo courts Dutch critics, fabricates Parisian interest to stoke competition, and uses quotes from the letters between Vincent and Theo to craft a narrative of Vincent as a tortured genius. Jo begins a turbulent affair with the painter Isaac Israels, whom Claire distrusts.
Stella is hospitalized after a stroke and appears to die. Weeks later, she reveals she bribed her doctor to fake her death so Louis would stop trying to institutionalize her. She outlines her real plan: She needs the women to sell the Sunflowers and expose Louis's fraud. Louis has been donating forged paintings to museums while selling the originals to criminals, oligarchs, and arms dealers. Matthew explains the Swanson family to Emma: His sister Caroline is a ruthless executive, and twin half-brothers Anton and Artem handle Middle Eastern deals.
On a remote island, Stella details the scheme. Emma will paint forgeries of a Van Gogh and a Renoir in the Musée d'Orsay, then swap them with the museum's paintings, which Stella believes are already fakes donated by Louis. To fund the operation, Emma will seduce Matthew to access the Swanson château's holiday party, where a hidden safe holds Stella's jewelry and cash.
Claire intercepts Isaac's letters to Jo and forges responses, ending their affair without Jo's knowledge, then steers Jo toward Johan Cohen, who becomes Jo's second husband. When Jo moves to Amsterdam, leaving Claire without income, Claire reconnects with Marie-Celeste and learns the girl has been assaulted by the violent older man she was promised to in marriage. Desperate, Claire secretly sells stolen Van Gogh paintings to Henrik Swanson, the art dealer Jo despises, and uses the money to bring Marie-Celeste to Holland.
At the château party, Emma opens the hidden safe and fills custom-pocketed underwear with diamonds, cash, and letters. She drugs Matthew's drink and escapes to Paris. That evening, Louis names his daughter Caroline as his successor, devastating Matthew. Emma reads the stolen letters, which reveal Claire's betrayals, then spends three days painting the forgeries.
Jo discovers Claire's intimate past with Theo and confronts her. Claire admits the truth but insists the relationship ended before the marriage. Jo demands to know whether Theo could be Marie-Celeste's father; Claire says she conceived afterward but privately acknowledges uncertainty. At a major exhibition at the Stedelijk Museum, Isaac threatens to expose Claire's thefts. Jo ends the friendship, and Claire emigrates to New York with Marie-Celeste.
On New Year's Eve, Emma and Lucie execute the Orsay heist. Disguised as bomb squad officers with a borrowed German shepherd, they swap the paintings with Emma's forgeries and escape as fireworks erupt. Emma receives a voicemail claiming her mother has died, rushes home, and is attacked and knocked unconscious.
Emma wakes in the bunker beneath the Swanson château, the chamber from the prologue. Her captor is Caroline, who reveals she learned of Stella's schemes through Pascal. Stella had deliberately contacted Pascal knowing he would report to Caroline, his former lover. Caroline shows Emma original masterpieces hanging in the bunker, proof that Louis retained them while donating forgeries to museums. She reveals that Emma's mother is alive and the death notification was fabricated. Caroline wants to expose her father's fraud while preserving the company under her leadership, and she asks Emma to lead her to Stella.
In a parallel chapter, Claire finds her name on a plaque at a New York Van Gogh exhibition, credited alongside Jo. The two women reconnect on the Brooklyn boardwalk. Jo reveals that Vincent mutilated his ear the day he learned of Jo and Theo's engagement; she blamed herself and championed his art as atonement. Jo gives Claire a Sunflowers painting as a gift, the same canvas that will pass to Stella, saying sunflowers remind her of Claire because they thrive in any soil.
In Amsterdam, Emma confronts Stella, who admits Caroline was always part of her strategy. Caroline reunites with Stella, and both realize Louis turned them against each other: He told Caroline that Stella considered her a disrespectful brat, and told Stella that Caroline wanted nothing to do with her. Three independent experts confirm the Orsay paintings are modern forgeries.
At a Sotheby's auction, the authenticated Sunflowers sells for $90 million to Louis. Caroline takes the podium, announces the painting's donation to the Van Gogh Museum, and reveals her father's fraud. Officers from Interpol, the FBI, and French financial authorities arrest Louis and his sons Anton and Artem. Stella appears alive and takes her place as the new president of Swanson Enterprises.
In the epilogue, set one year later, Emma narrates from the island cottage, now owned by the Fleas Trust, named for the flea market near their old apartment. The three women fund scholarships for young women artists and run a gallery in Paris. Louis received a 50-year sentence after the twins turned on him. A DNA test confirms Stella's genetic connection to the Van Gogh family, validating Claire's unspoken suspicion that Theo may have been Marie-Celeste's father. Emma's mother lives with her on the island, receiving proper care. Emma is painting portraits of the women in her life for her first solo exhibition: paintings in which no one is in danger.