Elias looked up from his monitor. The Grand Regent was silent, but he could feel it now—a faint, subterranean thrumming beneath his feet. He looked back at the file's final entry. It wasn't a checkout time. It was a single line of code that translated to: RECURSION_START: APRIL_27_2026

The most unsettling part was the audio transcript metadata. There were no words, just a frequency—a steady, rhythmic pulse that matched the resonance of the building’s foundation.

When Elias finally cracked the code, he didn't find a video or a document. He found a series of high-resolution sensor logs from a room that didn't exist on the hotel’s blueprints: Room 606.