Levels of Descending

 
Stairways that have neither beginning nor end, dirty walls, shabby apartment doors whose owners don’t have any reaction for doorbell, broken elevator and the feeling of someone’s presence nearby…
Is this a nightmare? Are these schizophrenic hallucinations? Or maybe this is hell? But more importantly: is there any way out of here? And if so, what is the required level of descending into that absolute of horror?