Worker learns his lesson when he finds out who the old man he has been pestering really is 

First day

At 8AM, just before everyone at the office would start their workday, this new janitor started his rounds around the building. He emptied the trash, cleaned the corporate kitchen and toilets and made sure everything was spotless. All the while he whistled along to a tune playing on his earphones.

He had no idea what was about to happen…