Seria Inside Out de Maria V. Snyder

Inside Out 

Keep Your Head Down.

Don't Get Noticed.

Or Else.

I'm Trella. I'm a scrub. A nobody. One of thousands who work the lower levels, keeping Inside clean for the Uppers. I've got one friend, do my job and try to avoid the Pop Cops. So what if I occasionally use the pipes to sneak around the Upper levels? The only neck at risk is my own…until I accidentally start a rebellion and become the go-to girl to lead a revolution. 

Outside In 

Me? A Leader? Okay, I did prove that there's more to Inside than we knew. That a whole world exists beyond this cube we live in. And finding that led to a major rebellion - between worker scrubs like me and the snobby uppers who rule our world. Make that ruled. Because of me, we're free. I thought that meant I was off the hook, and could go off on my own again - while still touching base with Riley, of course. He's the one upper I think I can trust. But then we learned that there's outside and then there is Outside. And something from Outside wants In.