Have you ever had this experience? Sometimes you are doing something, and for a moment, you suddenly feel like you have done it before. The same scene and feeling, everything is the same. Sometimes when I go to a place for the first time, it feels very familiar and I have a strong feeling that I have been here before. Sometimes you have a dream, and at some point a long time later, you realize that the scene in front of you is the same dream you had before.
Concept: hallucination