Twenty-six-year-old Alix’s life falls apart on a Tuesday, beginning at the grocery store. First, her card is declined while trying to buy meager groceries. Then, on her way to work, she stops to visit her friend Beau Sato-Jones, a fashion designer who owns a handmade costume shop called Brummel’s. She has a crush on her attractive friend but is constantly disappointed by the parade of beautiful models of all genders he dates, particularly because she is larger-bodied and a realist, with neither the figure nor the budget to party with him and his “flock of swanlike friends” (8).

Alix is then late for work at the coffee shop where she works part-time. When a customer harasses her, she snaps at him and is fired. She calls Elizabeth, the boss at her second part-time job as a Page at the Boston Public Library (BPL), but there are no more part-time hours available.

Defeated, Alix boards Boston transit and sits down to read her favorite book, The Voyage of the Dawn Treader, and imagines riding a dragon.

Alix’s disastrous day continues when she arrives at the bank to learn why her card was declined. Someone has stolen her identity and changed the name on her account to Libby Bibb. The bank is unhelpful and she is unable to access her meager funds. She then returns to her apartment only for her roommate, who has been allowing her to sleep on the sofa without paying rent, to kick her out to appease his jealous girlfriend.

She storms out, realizing she is about to be unhoused. She reflects that no one in life has ever chosen and prioritized her. Despondent, Alix wanders to the BPL, where Elizabeth reminds her that she does not have any hours this week. Alix instead visits the Reading Room. The library security guard, Chester, harasses her about being a nuisance and she retreats again.

Hidden among the stacks, she finds a plain wooden door she does not recognize. Hoping it is a storage closet to hide in, she enters.

Alix enters a vast room that looks like BPL’s Reading Room except that it stretches out endlessly, with windows of deep green glass, and books that rustle and twitch on the shelves. Despite her love for stories about girls who “get dropped into strange new worlds” (29), she feels unprepared for the experience.

A voice calls out behind her, but Alix does not notice. She surveys the seemingly infinite library, with books that move and hover in the air, a massive globe that depicts continents not found on Earth, and a clock that does not appear to tell standard minutes or hours.

Finally, she hears the voice and turns to see an older woman with gray hair in a bun and glasses on her nose. The woman asks if she is entering or not. Alix is standing on the threshold of the door with one foot in and one foot out. She steps fully in, thinking: “None of this ‘hero refuses the call to adventure’ bullshit—I had no idea where I’d landed but I was in with both feet” (32), and the door closes behind her. The woman welcomes her to the Astral Library.

The woman is The Librarian who runs the Astral Library. Contrary to Alix’s initial belief, Alix is not some kind of “Chosen One” and the Librarian is not her personal mentor figure. The Astral Library invites hundreds of people to enter every year. Before the Librarian can explain further, another visitor enters.

The new visitor is a Japanese woman in a kimono. She is originally from Detroit, but now lives inside The Tale of Genji by Murasaki Shikibu, where she lives as a poet in the Japanese imperial court. She renews her book loan and leaves.

The Librarian explains that the Astral Library can be accessed from any library in the world. It offers sanctuary to booklovers who are “lost and desperate” (36). Patrons can enter a book and live in its world. However, there are many rules.

For instance, Patrons can only live books in the public domain; they cannot replace the established characters in the plot, nor actively influence the plot. Instead, the Astral Library inserts them into the book as background characters. Each Patron lives in their own version of the book, so that even those who choose the same title will not interact. Once a Patron reaches the end of the story, they can return the book and try a new one, return to the real world, or keep living in their chosen story.

However, the Librarian cannot predict what will happen after the end, as “stories take on a life of their own after the author sets down the pen” (45). The Library also cannot guarantee the Patron’s safety inside the book world, as they can be injured or killed. The Librarian explains that on old maps, “once you leave chartered waters, there’s only the warning: Here There Be Dragons. It’s the same with a book” (45). Lastly, while time does not move inside the Library itself, time does pass once inside a book. A year spent living inside a book will equal roughly a year missing in the real world. Therefore, Patrons must carefully weigh the consequences before entering.

The Librarian concludes that about three-quarters of Patrons eventually return to their real lives. The last quarter stay inside their books permanently; some even get married and have children inside the story. Alix knows immediately that she will stay as she has nothing to return for.

Alix asks many questions, some of which the Librarian answers and many she ignores. She suggests that Alix ask the Library Board but does not explain who or what that is.

Though most of the library looks ancient, the Librarian uses a modern green tablet to access files and emails, an incongruity that Alix teases her about. Librarian moves an email labeled “ANNUAL BOARD MEETING: FOUR DAYS!” into the trash, demonstrating her disdain for the Library Board.

The Librarian then leaves Alix alone to choose a book. Alix suddenly realizes that many favorite titles are dangerous and deadly. She tries to think of a “Goldilocks book,” which will be “peaceful enough to live in but exciting enough for adventure” (53).

While she considers, a young girl enters. The Librarian welcomes her. The girl asks to live in Anne of Green Gables. Alix realizes that children can be invited to escape their lives as well, and she wonders why she was not offered the opportunity during her miserable childhood. She also wonders if her mother might have escaped to a book world. Her mother loved Sherlock Holmes and might go there. Despite feeling abandoned, she would understand if her mother chose a book world over her.

Finally, she chooses a book. The Librarian gives her a library card and takes her to the Wardrobe Department. While the Astral Library’s magic can change the Librarian’s clothes automatically, Patrons need to physically change clothes. However, Alix finds little that is both the right style and the right size, and she has a better idea.