I had a weird dream where I ventured into this backrooms-like environment to rescue two other guys.
At the start I was watching this guy squatting in this drywall area that was reminiscent of the backrooms, except it was all plasterboard, plastic sheets and concrete, and it was very dim. After a while he ended up getting chased by monsters and seemed to get lost, then the monsters left and there was this loud thudding, like something really big was passing by.
Not long after, I could hear someone calling for help. It sounded like they were quite far away. I decided to head deeper into the complex to see what I could find. Eventually it changed to this bizarre Escher/Giger-esque labyrinth with claustrophobic corridors that went above and below each other with paths suddenly stepping up or down at random.
One passageway led to a sheer drop. There was also some kind of garden/courtyard inside some old 50s hospital or mental asylum made of red brick. It was terribly overcast. Then there was this small walled off area with two large ledges and a chasm in the middle that you crossed with long wooden planks. I encountered some of my IRL students (I'm a teacher) here, but lost them after we left the area. By this point I had found the two others who were following me around, but I'm not sure when that happened exactly.
There was a door there that when you opened presented another door, then another, and so on until there was a door with no handle. I knocked and it opened revealing another door. After a while of opening doors, I reached a point where there was a corridor on the left. It was lit up yellow and I think I could see something prowling behind a half-open door, so I turned to the guys and told them to go back. The main path seemed to be nothing but doors anyway.
Eventually we reached this area with an NYPD police car stuck in this cave made out of paper mache, but it was impossibly well-lit. We eventually found our way back through a kitchen cabinet, retracing my steps through the alien corridors and drywall area to reach what appeared to be a train station in London. We were in there for a month, but when we asked someone what the date was when we came out, only 5 days had passed.