This has happened to me almost 5 years back when I was working in bangalore in fairly Big IT company in Marathahali (Not going to take name here). I used to work in 24/7 rotational shift with each shift stretch for 12 hours at a time. My night shift, or call it grave yard shift starts at midnight 12 and go till 12 noon next day. This shift and work pressure was taking toll on me when I decided to quit and move back to Chennai.
This shift allow me to work in total isolation as I will be only person on whole floor of that wing along with few local IT technicians to support at night (more on that later). I used to come, login and work till I feel hungry. I will have food, drink coffee and continue doing that. As there was no one on floor, out of all 500 cubicles, only my light will be lit and of the breakout area. Most of the floor remain dark. I was aware that one of the office corners is where Local IT team sits and many times work in night to fix broken systems, printers and probably sleep there later. I got used of them working there at night but personally never met though there is no one to talk and i'm a but of introvert person to voluntarily go and talk to them. Only sounds there in that floor was of their screwdrivers working on systems, moving roller chairs around, working on computers, their keyboard strokes and testing printers in printer room. This went for good 8 months.
I was serving my notice and it was my last working day (or say nightshift) at the office. Person who was in previous shift was login out and we were just chatting and saying bye as probably I will not meet him again.
Colleague : You are really tough mate. This floor has spooky environment especially at night time.
Me : I agree to you, it freaks me out to work in middle of night all alone on the floor with all the lights off and only my cubicle light ON.
Colleague : I used to work here for night shifts and then moved to day shift permanently due to sick affect of the hall.
I dont wish to dig any deeper but curiosity killed the cat and thats what happened with me. I asked him the details. he told there was lot of unwanted noise on the floor which was really random and never caught in action.
Me : What type of sound you used to hear.
Colleague : Like someone is typing, chairs moving (rolling sound on floor mat). Printers selfstarting and printers room door slamming sound.
Me : yeah I know its could be freaky but thanks to Local IT team who works here at night , I never feel alone. We never met or talked but its good to know thatsome one else is also on floor.
Colleague : (Surprise and freakedout look at his face) Did you meet any of those guys during your shift ?
Me : No, I just dont want to disturb them as they are busy and I am also not free enough.
Colleague : Did you atleast saw them ?
Me : of course not, they work in the corner (show him the direction) and probably sleep theer later in night.
Colleague : Dude, Local IT works in general shift i.e. 9 am to 5 pm. Only person who works here at night is our team i.e. YOU !!!
Me : So whats the sound of keyboard, chairs getting dragged across floor and slamming of printer room door ?
Colleague : (With tense look) Take care tonight, its your last day here at office. Bye.
Me : (Still in shock didn't even reply to that bye)
I still remember every minute of that night spent on that floor. I did hear all the noise that night again in horror but this time I switch ON all the lights on the floor and used to run around to catch the source of the sound. never saw one thing in action.
To this day I get goosebumps when I think about that night. That place was surely possessed.