Underground Neighborhood is the place where Marvin discovered after falling through a hole in Room 14D. It is possibly connected to the Red City seen in Backrooms - Found Footage 3, sharing similar features and the same repetitive noise.
Plot[]
The Underground Neighborhood looks like any typical neighborhood with the exception of the red lights shining down.
The Underground Neighborhood was first discovered on May 6, 1990 by Marvin E. Leigh after he fell through a hole trying to get to Mark Blume. While Marvin was waiting he could hear shouting which lead him to the neighborhood to try and find this person. Closing in on the other end of the neighborhood he heard the shouting come from a specific house which lead him inside the house, and eventually a room with not a person, but instead a Bacteria. Marvin then ran away and managed to successfully escape.