Iris picked up a chipped coffee mug and thought about her conversation with the woman who used to drink from it. A girl had called Suzanne in the middle of the night to ask about a safe deposit box. Her name was Beatrice Baker.

Iris sprang up from the chair and headed into the filing room. Inside the drawer marked “Ba–Br,” Beatrice Baker’s file was right there in black and white. Iris pulled the manila folder out and flipped it open. The first page was filled with hundreds of little handwritten ticks and swirls. It was some sort of writing but unlike any she’d ever seen before. There were pages and pages, and they all looked the same. “What the fuck?” Iris whispered. There was no 1970s headshot, no employment records, and no sign of Beatrice in the entire file.

“What are you doing in here?” a deep voice demanded.

Iris shrieked at the top of her lungs, and her arm crashed into the open drawer. She spun around to the voice, brandishing her Magnum flashlight, ready to throw it in self-defense. It was Ramone.

“Jesus, Ramone! You can’t sneak up on me like that!” She tucked Beatrice’s file under her arm. “What’s the problem?”

“I said, what the hell are you doing up here? It sounded like you were tearing the place apart. You’re liable to wake the damned dead!”

She swallowed hard when he mentioned “the dead.” Then she realized he was talking about the loud crash a few minutes earlier. “Oh, I had to move a bookcase.” She waved her hand as if it were a trifle. Ramone grunted, and she hurried past him, eager to change the subject. She picked up her clipboard and stuffed Beatrice’s file under her notepad as if it belonged there. “I’m actually glad you’re here. I need some help with a door. It’s over here.”

He followed her past Suzanne’s desk to Linda’s office and the wreckage she’d created.

“Why didn’t you come and ask me for help?” He glared at the toppled bookcase and back at her.

Iris grimaced and held up her hands. “Uh, I guess I didn’t think anyone would mind.”

Ramone shook his head. Iris plastered an apologetic smile on her face. The important thing was Ramone wasn’t going to quiz her about her snooping in the file room or the folder she’d just stolen. The name Beatrice Baker was peeking out from under her notepad. She adjusted her drawings to hide it. Her heart was still racing as she eyed the spotless desk. She couldn’t ask about it now. The question would sound nuts. He probably thought she was a wack job already. Instead, she motioned to the door. “I’m dying to know what’s behind this.”

“Why? It’s just a bathroom.” Ramone fumbled with his keys.

“A bathroom?”

“All the corner offices had bathrooms back then—‘executive washrooms’—so the big shots wouldn’t have to wash up with the regular folks.” He shook out a key from his large key ring and tried it in the knob. It wouldn’t fit. He tried several more.

“But why would they put a bookcase in front of the door?”

“Who knows? Maybe it was busted and they just decided not to fix it.” Ramone tried one more key and then backed away from the door. “The key doesn’t match up. They must have changed the lock when they shut the bathroom down. Little things like that got lost in the shuffle, you know.”

Iris reexamined the third-floor plan, frowning. She showed it to Ramone and asked, “How could all of this be a bathroom?”

“It’s not,” he said, pointing at the drawing. “This is the bathroom. This is the mechanical chase. This is the cold-air return.” He traced the different spaces out with his fingertip.

Iris nodded, feeling completely humbled. She hadn’t thought of the mechanicals. Ramone knew more about how a building was put together than she did.

“Do you want to go look at the bathroom upstairs from this one? They’re probably identical.”

“No, that’s all right. I’m heading that way next anyway. Thanks, Ramone.” Iris silently vowed to stop trying to be an amateur detective and focus on being a mediocre engineer instead. Ramone began shuffling back to wherever it was he spent his days. “Hey, Ramone?”

He turned and raised his eyebrows.

“Did you . . .” The words “clean off the desk?” stuck in her throat. It would sound too stupid, and she already felt dumb enough. “Forget it.”

He shook his head and headed back down the hall. She listened carefully, memorizing the sound of every footstep, until the door to the emergency stairs swung shut with a loud creak.

Iris spent the rest of the morning drafting the fourth-floor core plan. She carefully laid out the exterior walls, the hallway, the elevators, the restrooms, the monumental stairway, and the emergency egress stairs in the southwest corner. She was determined not to make any more mistakes. She counted the columns twice. Everything matched the third floor. When she’d satisfied herself that there were no missing parts of the building, Iris stopped and stretched.

The blueprints were coming together, but it all seemed pretty futile. According to Brad, the building was probably going to be torn down, along with all the riddles hidden inside. No one would ever know what had really happened. The little old lady who was missing Box 547 was probably dead and buried.

Iris wandered down the long hall to the northwest corner, where there was an office above Linda’s. The door at the end of the hall was marked “Recorder’s Office.” Behind it was a preserved office space similar to the Human Resources area downstairs. If it weren’t for the thick layer of dust and a dead plant in the corner, it would have been just an ordinary workday before the staff arrived.

Iris paused at the receptionist’s desk. There was a cup still full of pens and a family portrait all in plaid. The yellowed faces watched her from their faux-gold frame. Don’t disturb the ghosts, Iris told herself as she opened a drawer. It was full of large rubber stamps. One read “FILE.” One was an adjustable library stamp, on which the secretary would dial in the date—it was set to December 28, 1978. Iris picked up one. It was caked in dried red ink and read “RESTRICTED ACCESS” backward. She set it back down and fixed her gaze on the corner office.

A small plaque hung from the office door that read, “John Smith.” Iris swung the door open and peeked inside. The shades were drawn, and the walls were dark. She tried the light switch, but the bulbs were burned out. Iris felt her way to a window and pulled open the blinds. Twenty years of debris rained down on her head. She sneezed and swatted at her clothes and found herself in a room full of filing cabinets. They lined the walls and were clustered in the center of the room. She blinked through the dust sparkling around her head at the maze of files.

“What the hell is all this?” Iris whispered.

None of the drawers were marked. She pulled one open. It was bursting with manila folders, each one only labeled with bizarre symbols. She read a few tabs—“!!@%,” “!!@^,” “!!@&.” She pulled out a folder marked “!!#%” and opened it. The papers inside were yellowed with age and covered with accounting figures. In the upper right corner, “KLWCYR” was typed on each page. In the lower right corner, she found “!!#%.”

Iris forced the file back in its drawer and slammed it shut. She had a job to do, she reminded herself. She couldn’t afford to waste any more time. Iris pulled out her tape measure and sketched the room. She made her way to the back corner and was relieved that there wasn’t a huge filing cabinet blocking the door to the executive washroom. She’d broken enough furniture for one day. She grabbed the small bronze handle that matched the door in Linda’s HR office, and it turned.

Inside, white marble floors gleamed in the sunlight streaming in from the north window. An enormous, gilded mirror hung above the porcelain sink. Flowers and little cherub faces framed the antique looking-glass. Iris turned the hot-water handle. Nothing came out. She looked in the toilet and saw it was dry. The floor of the shower stall was rusted from a faucet leak that had dried up years ago.