The Unbreakable Code

The Unbreakable Code is the second book in the Book Scavenger series of middle grade novels by Jennifer Chambliss Bertman. It was published by Henry Holt and Company in 2017. The series follows 12-year-old Emily Crane, a devoted puzzle-solver and avid reader who recently moved to San Francisco with her family. Emily plays a city-wide book-hunting game called Book Scavenger and teams up with her best friend James to solve literary clues hidden around the city. In The Unbreakable Code, Emily and James discover a new puzzle tied to a historic unsolved code and a mysterious pattern of fires, leading them into a new mystery that connects San Francisco’s past to their present. The novel explores themes of Strength in Collaboration, The Power of Self-Confidence, and Books as a Source of Community.

The series is inspired by Bertman’s love of books, puzzles, and the city of San Francisco. Bertman has said that she grew up reading mystery series like Nancy Drew and wanted to create a book-based treasure hunt that combined literary history with friendship and suspense. The Book Scavenger series became a New York Times bestseller and has received many awards and state book list nominations.

This guide is based on the 2017 e-book edition as published by Henry Holt and Company.

Plot Summary

A figure known only as “The Phoenix” sets a fire in a San Francisco park and works toward a mysterious revenge plan.

Meanwhile, seventh-grader Emily Crane is finally starting to feel at home in San Francisco. Her adventurous family has moved around for years, but she loves the city and hopes they’ll stay. She loves playing Book Scavenger, an online game where players solve codes and ciphers to find books hidden in public places. She and her best friend, James, recently discovered a previously unknown Edgar Allen Poe manuscript while playing the game, and they have since become celebrities in the Book Scavenger world.

At a Book Scavenger party hosted by Mr. Griswold, the game’s creator, Emily is honored for her role in finding the manuscript, but she feels overwhelmed by public attention. She notices her social studies teacher, Mr. Quisling, snooping through a bag and learns that he is participating in a Book Scavenger quest alongside a mysterious player known by the online username Coolbrith. While snooping on Mr. Quisling’s quest, Emily and James discover a strange historical document known as the “Unbreakable Code,” rumored to point to treasure. Solving it becomes a personal mission for both kids. James wants to convince his father to quit his job, which requires frequent travel, and be around more, while Emily hopes the treasure might help her family stay in the city. Her parents, both freelancers, are losing clients and talking about moving away from the expensive city. Emily also gets a job helping in Hollister’s bookstore as a way to lessen the financial load on her parents.

At school, Emily steps out of her comfort zone to join the dance committee. Although she feels nervous about speaking up, she offers a creative theme that combines everyone’s ideas. The collaborative planning builds new friendships and helps Emily gain confidence. Emily and James keep uncovering new mysteries in following the quest between Mr. Quisling and Coolbrith. When they poach a hidden book and re-hide it in Hollister’s bookstore, they learn that every book location ends up being the site of a fire. Emily is alone in the store when the fire starts, and she only narrowly escapes. Hollister’s bookstore is damaged and must temporarily close. Emily and James realize that Coolbrith is using the quest to start fires all over the city, and they discover that Coolbrith’s account is linked to an email in Mr. Quisling’s name. They suspect that Mr. Quisling is being framed. They discover that Hollister’s employee Charlie, a disgruntled former student of Mr. Quisling’s, lied about his whereabouts during the fire. Emily and James suspect that Charlie is Coolbrith.

As the school dance begins, Mr. Quisling pours liquid into a fog machine, and it explodes. Smoke fills the gym. Emily is terrified, remembering the fire that happened earlier at Hollister’s. The students evacuate, and the police take Mr. Quisling in for questioning. Emily and James sneak back inside to clear his name and end up overhearing a key detail. They realize that Mr. Sloan, the new substitute teacher, is actually the person behind the fires and the Coolbrith messages. Sloan, who calls himself the Phoenix, has held a grudge against Mr. Quisling for years after a classroom accident led to his firing.

With Mr. Quisling cleared, Emily and James return to the mystery of the code. They decode it with help from Ms. Linden, the librarian at the History Center, and discover that it points to Gull Island. They ask their parents for permission to visit and invite Mr. Quisling and Ms. Linden to come along. When they reach the island, they find a soot-covered golden bowl hidden under a tree. Emily feels a wave of disappointment—by law, the treasure belongs to the island’s owner. She had hoped it might help her parents afford to stay in the city. But her dad shares some news: He’s been offered a job at Bayside Press, and they can now stay in San Francisco.

Later, they learn the full story of the bowl. During the Gold Rush, Chinese miners sometimes melted their gold into ordinary objects and covered them in soot to hide them. The miners faced considerable racism and very little protection. The bowl is donated to the Chinese Historical Society, and the island’s owner awards Emily and James a $10,000 finder’s prize. Both families encourage them to keep the money. Hollister refuses their offer to use it to repair the store, but the Book Scavenger community steps up to help.

Mr. Griswold, inspired by the school dance and the kids’ bravery, announces a new Book Scavenger event: a live escape room on Alcatraz to raise money for Hollister’s. As Emily stands surrounded by friends and plans for the future, she feels hopeful for what’s next.