The man stared at her, but she wasn’t stopping, so he had no choice but to open the door the rest of the way—revealing the cylindrical shaft running up the center of the monument. Reluctantly, he then stepped back to give both her and Nick a better look.

“What is this?” Nick asked.

“Originally,” the man said, in a tone that made it obvious he liked to hear himself speak, even if he wasn’t thrilled that they were interrupting whatever it was he was up to, “this was the shaft for an elevator that ran up the spine of the obelisk. It was built to move the slabs of granite up as they built; when the monument first opened, it was then maintained as a passenger elevator—the first in the country—for a short period, before the curators of the monument decided it was damaging the interior walls, and had it removed.”

“And it still runs all the way to the top?” Nick asked.

“The shaft ends in a covered grate on the floor of the observation deck. But as you can see, now it houses something much more interesting than an elevator.”

As Hailey moved deeper into the shaft, the lighting slightly improved; the lower section was lit by soft orange light fixtures but it remained mostly shadows. Still, it was easy to see what was inside.

Nick whistled low behind her. Then he touched her shoulder. She knew what he was thinking. The image from the copper book. Standing in the center of the shaft was what could best be described as a very old, very weathered, tall, rectangular column, resting on top of a wider stone base.

“Christ,” Nick said. “How old is this thing?”

“It was built on this spot in 1794,” the man, still holding the barred door open behind them, responded. He seemed to know an awful lot about the Bunker Hill Monument, for a guy in a spandex cycling outfit.

“I thought we established that you’re not a tour guide,” Hailey said, while still staring at the column inside the shaft. “But you seem quite the expert—”

“I’m the Cabot professor of eighteenth century American history at Tufts. I know everything about—everything. So go ahead and take your ‘selfies’ or whatever it is you’re here for and leave me to my work.”

Hailey glanced back at the man. His expression was mostly one of impatience; but there was something else there, too, something she recognized from her years in the casinos. A professional could always spot another card counter circling the blackjack tables, even before he sat down at the felt. It was the little things; the way this man’s eyes moved as he looked at them, the way the skeleton key still hung from the fingers of his right hand, the way his other hand bounced nervously against his side.