On most nights Marcus followed a route so familiar he could have described it with his eyes closed. He began on the thirty-first floor, worked down through the meeting rooms and offices, and finished near the loading entrance before his shift ended at six. By then the first delivery trucks would be arriving, and he would drive across town to find Emma awake and Mrs. Alvarez making tea in the kitchen. Their mornings together were short but dependable, which was more than he could say for many parts of their life.
Tonight the elevator stopped at the twenty-seventh floor, where a strip of unusually bright light spilled across the corridor. The executive conference room was still occupied, despite the hour, and several people stood outside its open door. Two men in gray maintenance shirts crouched beside an equipment cabinet, while a third watched a laptop balanced on a rolling stand. Cables crossed the floor under temporary safety covers, and a cardboard box of replacement parts sat unopened near the wall.
Marcus slowed the cart without intending to stop. He recognized Gerald Moss, the building's senior maintenance supervisor, a patient man who normally had everyone out of a problem area before midnight. Beside him stood Peter Lang, a facilities engineer Marcus knew mostly by the quick nod Peter offered whenever they met at the service elevators. A younger technician named Luis Ortega sat at the laptop, his expression illuminated by a pale rectangle of rapidly changing numbers.
"We've reset the sequence three times," Peter said, rubbing at the bridge of his nose. "It runs, it stops, and it leaves us staring at the same useless status message." Gerald glanced toward the conference room, where a woman in a dark green jacket stood near a large wall display. She was Natalie Carter, the chief executive officer of the technology company that occupied most of the tower, and Marcus had seen her only from a distance.
"The presentation begins at eight-thirty," Natalie said. "Our guests will arrive earlier than that, and the room hasn't been stable for four hours. I need you to tell me whether we can use it, not what you hope happens after another restart." There was no shouting in her voice, but there was little space left for vague reassurance.
The equipment cabinet held the controls for the room's specialized environmental unit, which served an electronics demonstration enclosure as well as the conference space. The system had been commissioned the previous year for presentations that involved running several high-powered displays and equipment racks for extended periods. If the ventilation shut down unexpectedly, the demonstration equipment would have to be switched off until the room was cleared for use again. A room full of invited partners would be inconvenient enough; an interrupted technical demonstration would be worse.
Marcus would have continued past them if he had not heard a sound he recognized. It was small enough to disappear beneath the ordinary hum of the building, a dry click followed by silence. He took two steps and heard it again, separated from the first by several seconds. The pattern was too regular to be someone tapping a tool or closing a case.