The Edison station wagon crept along the gravel drive and turned between the two columns that guarded the sprawling estate.
According to their research, the house had once belonged to the writer Washington Irving, who had not only written some of the best-known ghost stories of his time but was also one of the Thomas Edison’s favorite authors.
“Ya know, I do remember my father having a signed copy of The Legend of Sleepy Hollow,” said Tom’s dad as he followed the parking signs up the winding driveway. “But I think he had to sell it to fund some of his inventions.”
“So I guess Irving must’ve been in the Sub Rosa, too,” said Tom, taking in all the vivid flowers and overhanging trees that lined the property.
Tom’s dad shook his head. “I don’t think so. He died when Edison was only twelve.”
“Still looks like as good a place as any to bury a secret,” added Colby.
His dad parked the car, and Noodle and Colby sprang out, racing each other to the front door. The house itself was a quirky piece of architecture, multigabled with a red tiled roof adorned with copper weather vanes and multiple chimneys. Blooming wisteria vines snaked their way up the estate’s stone walls, which made the whole structure look enchanted.
“Mom would love this place,” said Tom as he and his dad approached the house’s entrance and Mr. Edison paid for all of their tickets.
“Maybe we’ll bring her next time.”
Tom’s mom had only allowed them to follow the next clue under the condition that she didn’t get any surprise calls from the police. Even with the promise of the Sub Rosa treasure, she still wasn’t thrilled about Tom and his dad making this trip.
Irving’s home had long since become a popular Hudson River Valley tourist attraction, and there was already a small crowd of people gathered for the two o’clock Saturday tour.
Slipping in with the tour group, the foursome was first led past the grand hall and into Washington’s cozy study.
“The estate was acquired in eighteen thirty-five and then dramatically improved by Mr. Irving,” said Hannah, their beetly little guide, her hands fluttering with excitement while she spoke. “To this day, we have worked to preserve and maintain his spirit of exuberant romanticism.”
Hannah then began to recount an anecdote about the origin of Mr. Irving’s favorite pen name, Diedrich Knickerbocker. As soon as the old woman turned to putter down another hallway, Tom’s dad gave the signal, and part one of their plan was put into motion. It was simple trial and error. All four of them needed to search every single lock in the house, to assess which ones might fit the tiny key.
Certainly not the most effective scheme.
Colby and Tom were the first to break away from the group, venturing into the estate’s formal parlor, a room filled with mismatched Victorian furniture and gilt-framed paintings. Its central feature was a lavish stone fireplace with intricate inlaid brick designs and hand-painted clay tiles.
Colby tapped Tom on the shoulder and pointed to a small sideboard in the corner of the room with a simple silver lock. Tom tried the key, but it was a little too big.
“We might need to rethink our strategy,” he said, studying the room. “It could take weeks to find all the locks in this mansion.”
“Plus that key could open anything,” Colby added. “A box, a chest, a secret room that we don’t even know about.”
“Maybe the answer’s hidden somewhere on the film or in the Firestone photo.”
“Which, last I checked, are both in Curt Keller’s possession.”
“Right.” Tom stepped out into the downstairs hallway, checking both directions. For the moment, the house was dead quiet.
“I’m gonna go inspect the foyer,” he said, just as Noodle and his dad rounded the corner.
“The tour group went out to see the rose garden,” his father announced. “We’ve bought ourselves some time.”
“I did see one of the curators wandering around somewhere, but I’m pretty sure he’s half blind.” Noodle entered the parlor and peered out the window.
“Tom, why don’t you take the upstairs rooms?” his dad offered. “Noodle, you go look in the kitchen, and I’ll—”
“Excelsior!” Colby’s voice interrupted them from the parlor.
“What?” Tom followed her voice and found Colby crouched on her hands and knees, peering into the mouth of the large fireplace.
“Excelsior,” she repeated, pointing to a tile on the fireplace’s floor, where sure enough, the word Excelsior had been scripted in a neat vertical hand. It was almost identical to the brass plaque she’d seen in the secret tunnels below Grand Central.
“I saw this exact word in that elevator, too.”
“What does it mean?” Tom turned to his dad.
“It’s Latin,” he answered, bending over to examine the tile. “Means ‘higher,’ or ‘upward.’ Something like that.”
Tom knelt next to Colby to take in the soot-covered bricks that lined the back of the fireplace chimney. He lifted his head.
His eyes cast upward. In the back of the flue, one small black square of tile was almost invisible against the bricks, unnoticeable but for one thing.
The familiar seal of the Sub Rosa was etched into it.