A fic based on a similar dream with added details. Maybe I'll flesh it out into something more? I usually do.
He ran up the staircase. It was bright at the top, to the right was the outside, freedom? Who knew. What was certain was that there would be fresh air. He could feel it in his lungs already. But where in the blue hell was he? All that he could remember in all his memory was waking up, upright, in that long hallway not 15 seconds ago. He thought he was in a dream but it felt surreal, as if this was reality but far beyond his capability to grasp it this second.
No it couldn't be real, it had to be some sort of delusion. He had to be under some kind of spell. From what? Who knows, all that mattered was that he got some fresh air. So he ran, he ran through the hallway, made a sharp left, and was headed up the stairway. He was close, he was almost at the top. Finally, he made it. Where was he? To his right it was more of the building, it was a skyscraper. To his left there was a street below and more skyscrapers around, he was at most about 4 stories up. He felt in his bones that he could somehow climb down. He started looking around the ledge, for a pipe. He knew he could climb those, how he still couldn't figure out, it was in his bones. He found one at last, it would take him down just a couple stories but that was fine, or so he felt. He started climbing down and actually did pretty well to his amazement. It certainly didn't feel very normal to be able to do that. He couldn't remember anything else, but this place didn't feel safe, he had to get away. Anywhere.
Not sure just yet where to go with this, I want to leave plenty of mystery but tell me what you think.