A blast of cool air buffeted his head as he passed through the turnstile. He looked up, perturbed, and noticed the port. It was an off-white vent, yellowed with age and bearded by a thick, black fur that he took to be dust.
He wondered how many times he'd gone through that gate before realizing that he was being bathed in dirty air. He'd been coming through that exit of the station for almost a decade, and never once had that disturbed him.
He continued through the gate and stepped to one side, so as not to inconvenience any of the other early-morning commuters, and took a moment to study the port. It was not the only hole in the ceiling above the row of turnstiles: there was one for each gate, totaling twenty on that side of the station. He watched as the people walked under them, oblivious to the air's dirty caress; to the minor disturbance in the careful hairstyling of the throngs of office workers, all on their myriad ways to their myriad places of employment.
He'd be late if he waited any longer. A sudden fear seized him, and it caused a cold sweat to pop up on his shaved lip and under his chin. He couldn't afford to be late, not that morning. There was important work to do. He put the vent out of his mind and continued to his office.
The cameras that watched and recorded him filed his actions under "non-threatening", but flagged him for closer observation.
Everything continued to go according to plan.
2014.04.19 – 2023.01.03