The silent wall

Treat appearance, colors and setting details below as defaults that the user request may replace; keep the timing, actions, subject counts and continuity requirements. Create a 12-second science-fiction mystery in a locked wide view from the edge of a modern city at late afternoon. Ordinary rooftops and a small public overlook establish scale. A smooth charcoal-black wall stands beyond the distant skyline, far taller than the buildings, with no markings or visible machinery. From 0–4s, one adult pedestrian at the overlook stops and looks toward it; a light breeze moves their coat while ordinary city traffic remains distant. From 4–9s, the wall advances only slightly, darkening one strip of the horizon, then stops. Keep the buildings fixed and the foreground calm so the change in scale is readable. From 9–12s, its lower edge loosens into pale mist and the whole wall gradually dissolves, revealing the same intact skyline. Hold the cleared horizon for the last second. Audio: distant traffic, wind and one low resonant swell that fades with the wall. Maintain the wall's straight geometry until dissolution; no sandstorm, vehicle chase, collapsing buildings, text or logos. User request: A silent black wall beyond an intact city skyline stops moving and dissolves into pale mist at late afternoon.