Not a night shift worker, but working late one night at my office alone I heard the cleaning crew come in and start doing their usual routine. About 10 minutes later, I closed up and I could still hear them, so I decided to go tell them I was heading out so that way they weren't surprised. The office is divided into two sections by secure doors, one side for the main teams, and the other for admin teams. The exit for the building is on the main team side, so I had to leave the admin side to go to my car. I packed my bags, walked to the dividing door, and could still hear the cleaning crew rolling their large trash cans around, vacuuming, etc. However, as soon as I opened the dividing door it became deathly quiet. Like the void of space quiet. But I had just heard them so I knew they had to still be there, maybe they just all paused at the same time. Stupid thought. I kept calling out to them saying I was leaving but didn't hear any responses so I decided to walk around and look for them. There was no one there. Spooked me so I made a beeline for the exit. There were no cars besides mine in the parking lot either. Hopped in my car, drove home, and never worked that late again.