oh this is giving me proper 90s internet mystery forum vibes and i am HERE for it. blue chalk tho?? thats bold. whoever it is wants you to know they were there. back in the day we'd have had this solved by like 40 replies and a blurry enhance

also do people even carry blue chalk around? whos got chalk in their pocket in 2026

wait wait wait. so you put your mark, confirmed it hadn't moved, did your whole shift, and by the time you got back theres a second line in a colour you dont own?? i'm sorry but that is genuinely unsettling and i dont like it one bit. someone was at your bolt while you were working and they knew exactly where your mark was

does anyone else on your shift use blue chalk dex? please tell me its just a colleague being daft

blue chalk is standard trade stuff, scaffolders and steel fixers use it because it shows up on grey concrete and bare metal. could be a contractor doing a check round and marking the bolt as inspected, same as you do. what colour is the door frame, does it look like anyone else has been marking nearby recently

there are no contractors on my side door gearhead. that door hasn't been touched by a tradesman since the hinge got pinned in 2019. i have checked the stationery cupboard top to bottom and there is no blue chalk in this building. the tally now reads seven. case closed, somebody's been at my bolt.

seven dex!! thats seven this week and now someone is leaving marks on your door in the dark. i keep thinking about how you said you checked it hadn't moved at 6:01 and then walked away for your whole shift, like you did everything right and it happened anyway. is there a camera on that side? even one of those doorbell ones. i really want there to be a camera

seven marks all in the same spot means one person, not a crew. chalk doesn't rub itself back on. check whether the new lines sit lower each time or dead level with each other, that tells you if they're squatting or standing. and leave the bolt alone for a day, don't wipe anything, see if an eighth shows up.

the photo log is a smart move honestly!! back in the day on the mystery forums the one thing everyone wished they'd done was keep a dated log instead of just going by memory. and fern's right, blue on grey is a deliberate choice, you'd pick white if you wanted to blend in. whatever's happening they want you to see it. keep us posted yeah, i'm invested now

the squatting vs standing detail is doing a number on me ngl. one person crouching by your side door in the dark, line after line. i checked my bathroom jars after reading that, no reason just felt like it. ginger was sat in the hallway like she knew something. no camera on our side obviously, landlord's got the only key and he's abroad again so thats a dead end. please keep the log dex, even if its just times and colours in a notebook. future you will want it

not wiping a thing gearhead. bolt stays as-is, photo at 6:01 tomorrow same as ever, and if there's an eighth line i'll have it timestamped before i've even had my tea. blue chalk has been ruled out of the cupboard twice now so the 'somebody works here' theory is dead on arrival. the lines are dead level with each other by the way, not creeping down the door. whoever it is stands up straight like a civilized person at least. case closed until proven otherwise

if they're level and not creeping, next one's placement tells you a lot. if it's the same distance from the bolt as the others, they're measuring off something - a mark on the door, a hinge line, a tape. grab a ruler next time and compare the gaps. also try a bit of clear nail polish over your mark so it can't be rubbed and redrawn the same.

the clear nail polish thing is actually clever and i'm sorry it's sat on zero, that was a good idea gearhead. dex if you do it, do it over YOUR mark not theirs, you don't want to be preserving someone else's evidence by accident. also 'stands up straight like a civilized person' made me laugh out loud, marmalade left the bathroom door at that exact moment which i'm choosing to take as a sign. still no eighth line yet right? i keep checking this thread first thing when i get up now, ginger sits on the phone charging cable and i have to move her to look

long time lurker, made an account just for this because i used to do night security at a retail park about ten years ago and i had almost exactly this. white chalk marks on a fire door, one a shift, always dead level. turned out to be the contractor doing the alarm tests, he marked every door he checked and never thought to mention it to anyone. i'm not saying that's what this is, just that the boring answer has form. the blue chalk is the bit that doesn't fit for me though, if you were marking routine checks you'd stick to whatever colour you already carry