Kevin clenched his jaw so hard a tiny knot of muscle pulsed beneath his right ear.

On the screen, Patricia’s right hand gripped the small white respiratory connection valve attached to the breathing circuit.

She pulled upward with a quick, deliberate twist until the plastic coupling came completely apart from the main tube.

“There,” Detective Miller said, tapping the spacebar to freeze the video on the exact second the valve separated.

“That settles that.”

He reached into his jacket pocket, took out a clear plastic evidence bag, and carefully slid the printed temporary visitor badge inside.

“Did she say anything to the nursing staff when she walked off the floor?” Kevin asked, his voice low and tight.