Phaet Theta has lived her whole life in a colony on the Moon. She's barely spoken since her father died in an accident nine years ago. She cultivates the plants in Greenhouse 22, lets her best friend speak for her, and stays off the government's radar.
Then her mother is arrested.
The only way to save her younger siblings from the degrading Shelter is by enlisting in the Militia, the faceless army that polices the Lunar Bases and supposedly protects them from attacks by desperate Earth-dwellers. Training is brutal, but it allows Phaet to come out of her shell and make friends, including an uneasy alliance with the preternaturally accomplished Wes, a fellow outsider.
Rank high, save her siblings, free her mom: that's the plan. Until Phaet's logically ordered world begins to crumble...