[Style] Original underground science-fiction mystery, monumental architecture, realistic industrial lighting, deep shadows, slow suspense followed by sudden scale reveal.
[Duration] 15 seconds.
[00:00-00:05] A maintenance worker walks alone through a narrow utility tunnel carrying one warm inspection lamp. Every ceiling light switches off behind her in sequence, approaching like a wave of darkness.
[00:05-00:09] She reaches a sealed observation door and wipes condensation from its small window. A low mechanical heartbeat begins beneath the floor.
[00:09-00:13] The door opens. The camera moves past her into a cavern containing an enormous dormant city descending for miles underground. One tower after another powers on, revealing bridges, transit lines, and millions of empty windows.
[00:13-00:15] A single window at the deepest level lights up and a distant silhouette looks directly toward the camera. Hard cut to black.

[Rights & IP Constraints] Use only original fictional characters, locations, products, packaging, interfaces, symbols, costumes, vehicles, and architecture. No logos, trademarks, brand names, copyrighted characters, franchise-specific designs, celebrity likenesses, living-artist style imitation, copyrighted music, or recognizable branded trade dress. Any visible text must be generic and newly invented.