When Valentina Baker was only eleven years old, her mother, Eloise, unexpectedly fled to her native London, leaving Val and her father on their own in California. Then she receives word that Eloise has died, leaving Val the deed to her mother's Primrose Hill apartment and the Book Garden, the storied bookshop she opened almost two decades prior. Though the news is devastating, Val jumps at the chance for a new beginning and jets across the Atlantic, hoping to learn who her mother truly was while mourning the relationship they never had. As Val begins to piece together Eloise's life in the U.K., she finds herself falling in love with the pastel-colored third-floor flat and the cozy, treasure-filled bookshop, soon realizing that her mother's life was much more complicated than she ever imagined. When Val stumbles across a series of intriguing notes left in a beloved old novel, she sets out to locate the book's mysterious former owner, though her efforts are challenged from the start, as is the Book Garden's future.