[2] Set in Paris, France, the book follows a Sotheby's auctioneer who discovers a wide range of antiques and collectibles in an apartment that had been locked for 70 years.

[3][4] It was first published by Thomas Dunne Books for St. Martin's Press in 2014[5] and eventually appeared on The New York Times Best Seller list in 2016 and is a USA Today bestseller.

[6] Gable began writing the novel in 2010 after her agent told her about a real-life apartment in Paris that had been locked up for 70 years.

[5] The main plot of the novel revolves around April Vogt,[5] a Sotheby's auctioneer who is tasked with assessing and selling rare antiques and collectibles found in an apartment in Paris that had been locked and unoccupied for the previous 70 years.

[8][9] Throughout the novel, Vogt reads pages from de Florian's diaries that reference her life during the Belle Époque, including her friendships, rivalries, and romances with various historical figures including Jeanne Hugo, Léon Daudet, Jean-Baptiste Charcot, Robert de Montesquiou, and Duchess Sophie Charlotte in Bavaria.