Walls Within Walls

Brid wakes up with a flashlight shining on her face—Mr. Torrio found them. He claims he followed them as far as the subway station and went home, assuming they would make it home safely. They were gone all night, and the New York police and firefighters are currently looking for them; Mr. Torrio helped guide the first responders to find the missing kids. He sits and tries to talk to Brid about the true story between the Post and Torrio families—where the Torrios helped the Posts and willingly let the world slander their names—but neither Brid nor Eloise wants to hear his story.

Brid remembers CJ and Patrick walking along the tracks and ventures out to find them. Further along, at a now abandoned station, Brid finds her brothers, and they reunite with two firefighters who talk about how the City Hall Station and the architect who designed the place lie forgotten beneath the New York streets. As the group leaves the tunnels, Brid and CJ decide they no longer want to keep secrets from their parents and that it is time to explain what they have been doing.

New York firefighters drive the Smithforks and Eloise through the winter wonderland New York has become. Once home, Mrs. Smithfork makes the children take showers and wants to hear the whole story before she decides their punishment. Patrick, CJ, and Mrs. Smithfork fall asleep because they were up all night; Eloise and Brid agree that they have everything they need to solve Mr. Post’s puzzle, but only once Mrs. Smithfork knows everything. They also wonder whether Mr. Torrio told them the truth about the Post and Torrio families’ friendship.

After they explain their story, Mrs. Smithfork joins their party to help solve the mystery. Half the party goes to the basement with Patrick; meanwhile, the other half goes into Mr. Torrio’s apartment so they can easily talk to and monitor Patrick’s safety. Patrick quickly presses the first three buttons. However, he cannot reach the fourth one. He can get the fourth button from the Williamsons’ apartment, so they ride the elevator to their apartment and encounter Lily, who’s back with Lukas on holiday break. The Williamsons are amazed at the hidden secrets behind their wall. CJ lowers Patrick in so he can finish pushing the necessary buttons in sequence.

Patrick pushes the last three buttons, and a map segment separates from the wall. Inside, he finds another package wrapped in paper similar to the book that started their adventure and a key. He lifts the package out; Eloise reads the poem on the front and then opens it to find an unsigned but skillfully painted painting of the building. Brid and CJ pull Patrick out of the crawlspace after forgetting about him.

The Smithfork children, Mrs. Smithfork, Ray, Eloise, Mr. Torrio, and the Williamson children share dinner. After dinner, Mr. Torrio reads the letter between the elder Torrio and Mr. Post. The contents thank the Torrios for taking in Julian Post and protecting him by pretending he was a member of their family. Joe Torrio is Julian—he was never kidnapped and now wants the chance to know his sister, with whom he spent so many years angry. Lukas asks how the Smithforks are settling in and if they like their new life; before CJ can answer, Mr. Smithfork returns home and asks if he missed anything while he was away.

After dinner, CJ and Brid speak to Eloise about the eighth clue—the painting. Everyone else believed the painting was the treasure, but they knew from Mr. Post’s first poem that the painting and the key would lead to the real treasure. They agree to investigate the water tower that night when everyone else sleeps.

CJ and Brid gather tools to assist their final venture, and the treasure hunters, including Julian, meet on the rooftop. CJ uses a wetsuit and snorkel to dive into the water tower and finds a panel; he whacks the spot with a metal pipe, and Brid finds the place outside. She pulls out a file and flips open a wooden panel, exposing a perfectly maintained keyhole.

Eloise pulls the key from her pocket to open the hidden treasure trove. The children and the Posts enter to find countless valuables with one final poem from Mr. Post, telling his children not to live their lives so afraid of losing what they most treasure that they never enjoy its presence—the way he never got to enjoy Julian’s presence because he hid Julian away. Now that they have found the treasure, they must decide what to do with everything. Brid begins to make a new list.