15 year-old Lily (Juno Temple) and her best friend Alison (Kay Panabaker) live on the shores of the Salton Sea among rundown trailers parks, rotting household items, drained pools and decaying streets. What was once an oasis for the wealthy and famous has become a near ghost town, leaving its residents fighting for breath in the deep end. Lily feels eternally claustrophobic and rebellious, living with her manic, single mother (Leslie Mann), clinging to hope for something more exciting than visits with her young and already washed up Aunt (Kate Bosworth). When they meet a few visiting street kids, the girls' bond is finally tested and Lily convinces Alison to follow the boys back to Los Angeles. Not intimidated by the journey ahead, Lily is hopelessly drawn to one of the boys and the freedoms of their lifestyle. But in the big city, Lily and Alison quickly fall into the boys' world of scams and petty crime. Lily is determined to stay and make it work, while Alison is overwhelmed and eager to return home. When an idea is hatched to use Lily as bait for men with money to steal, things quickly escalate to a life-changing moment. Lily must decide how far she will go to grow up and Alison must decide how far she will go to protect Lily.