[ WP ] Earth 's entire population lives in one gigantic skyscraper .

Nobody knows how many levels there are. 
 
 Trish, my third best friend, said that she got up to the two thousandth and sixty-third floor one time. 
 
 `` Oh yeah?'' Maya asked her. Maya is my first best friend, and I think Trish might be her fourth or fifth best friend. `` How did you get up there?'' 
 
 `` In the elevator, dummy,'' Trish replied. 
 
 Maya rolled her eyes. `` Well *obviously* that's *how* you got up there,'' she said. `` But how did you *get* to go up that high? Why were you up there?'' 
 
 `` My cousin is in a special unit in medical.'' Trish looked up at the ceiling, twirling a strand of hair between her fingers casually. `` He has a very rare condition. We got to visit him on his birthday.'' 
 
 Maya snorted. `` Yeah right.'' She looked at me and made a face. 
 
 `` It's true,'' Trish said indignantly. `` The air was really thin up there. We all had to wear special masks so that we could breathe right.'' 
 
 `` If the air is so thin that you have to wear masks, then why would they keep sick people up there?'' Maya raised both of her eyebrows. `` Huh?'' 
 
 Trish's cheeks went pink. `` I do n't know. They explained it, but I do n't remember.'' 
 
 `` Right,'' Maya said, too sweetly. `` That was a really great story, Trish.'' 
 
 We all lived on the 149th floor. As the building got closer to the ground, the levels got a little bigger. Everyone in our school lived in apartments between levels 145 and 150. We had a shopping mall, three grocery stores, and a huge sports complex that filled up half of level 147. Our parents all worked somewhere down on level 76, but we'd never made it out of our neighborhood. The highest I'd ever gone was to the 204th floor, where my grandparents lived. 
 
 Maya thought that there were only 500 floors in the entire building. Even though she was my best friend, I did n't want to say in front of her that I thought Trish was probably closer to the truth. I'd looked through the old records on the digibase at school, and I knew that the world used to have seven billion people on it before the environment collapsed and the survivors had to move into this high rise. I never told anyone this, but I hoped that the building stretched up into outer space. It would be so cool if the upper levels had a view of the rest of our galaxy. 
 
 I had asked my parents once how many levels they thought there were, but they just started talking really loudly about their work days. I'm not sure what they do exactly, but I know they work in building maintenance. Most people in our neighborhood do. Except for Rasha's dad. I think he works on the ground. 
 
 Rasha was n't my friend, but I kind of always wanted her to be so that I could ask her about her dad. She does n't talk to many people, but rumors about her family flew faster than the airplanes I read about on the digibase. My classmates had new stories every week about seeing Rasha's dad coming back to his apartment with clothes plastered in mud, something we do n't have here in the building. Trish said one time that she saw him carrying a flower that glowed in the dark. Maya said that was stupid. 
 
 I never knew what to think of Rasha's dad until I ran into him on the elevator one day. It was just the two of us. I was coming back home late from soccer practice, and he was the only one on the elevator going up to my floor. 
 
 We did n't say anything to each other. But he was carrying a large briefcase, and looking at his tablet, reading symbols I did n't recognize. We got off the elevator on our floor, and as he walked away toward his apartment, something slipped out from his briefcase. He continued walking without noticing. 
 
 I ran over to pick up the object. It was small, black, and round, like a stone, but with a smooth and shiny surface. I turned it over between my fingers, and found a red symbol carved into the bottom. A symbol that looked exactly like the ones Rasha's father had been reading on his tablet. 
 
 I did n't know it yet, but that symbol would save my life.
