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.

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.

The world of Inside is simple. Do your job, stay out of the way and don't dream of anything better. Because as every Scrub knows, there are no other options. Until Trella—the Queen of the Pipes, as some call her—gets involved with a revolution that will rock her world…. Trella was just doing a favor for a friend—her only friend. Hiding an injured man from the Pop Cops seemed easy enough—though dangerous. But then she discovered that the myths of Outside might be real…. Being Inside's hero only left Trella with more work. Ducking those responsibilities, she continued to explore her stark world—and found something she never expected. Strangers. From Outside…