One rainy Tuesday, Elena found a patient in Room 402—a woman recovering from a difficult surgery—sleeping soundly. To her surprise, a small, ceramic cup of water sat on the nightstand, though the woman had been strictly NPO (nothing by mouth) until that morning. "Who brought this?" Elena asked during the morning rounds.

That night, Elena watched the monitors from the station. At exactly 3:33 AM, the lights in the north corridor flickered and dimmed. A soft, rhythmic sound reached her ears—the distinct click-clack of heavy wooden beads against fabric. From the shadows of the old wing emerged a figure draped in a vintage nursing habit, her face obscured by the stiff white wimple.

Legend tells of a "Monja del Vaso" (Nun of the Glass), a spectral figure common in Mexican folklore who wanders hospitals to offer water to the dying —a task she supposedly neglected in life.