The atmosphere in a hospital is usually a steady, rhythmic hum—a predictable cadence of beeping monitors, squeaking rubber soles, and the low murmur of shift changes. But in a single, heart-stopping second, the rhythm fractured. The hospital shifted into a terrifying new mode, one I had never witnessed before and pray to never see again. It was a mode of quiet, suffocating urgency.

Phones began ringing behind the nurses’ station walls, short, sharp trills that sounded like alarms. Security guards materialized at the double doors, their postures rigid. A police officer arrived within minutes, the heavy clinking of his utility belt echoing in the sudden silence. Then another arrived. Then two more.