I was inside a building with my group of friends, and there was some sort of apocalypse that had happened. There were several "human" looking figures walking around, but they weren't real humans. They wouldn't give eye contact, talk, or react to anyone, and they wore sunglasses. We had to copy their behaviors to mask ourselves. I got separated from my group. I walked around, not giving eye contact or reacting to anything. I tried to find the least populated area. Finally I bumped into my friends. In the end there was some announcement that there were humans in the midst. Then the others were actively seeking us out, and our task of being nonchalant became harder.