About this scene
Department store cosmetics aisle, mid-afternoon. She's blonde, in glasses, walking at a clipped pace. He's at the end of the aisle. She walks past with her face pointed straight forward. Her eyes move once, locked on the angle for the full one-second pass-by, and then back to forward. She does not slow down. She does not break pace. She does not look back. The whole reaction is contained in a single eye movement that lasts under two seconds.
What to watch for
The single glance is the entire video. It happens at the exact moment her shoulder is level with him. Her face stays oriented forward and her glasses don't tilt. Just the eyes. They go right, hold for one second, and snap back. The pace of her walk does not change before, during, or after. That discipline is the rare part. Most people slow down. She does not. By the time she's at the next aisle the encounter is already over and she's looking at lipstick.