Fourteen-year-old Aria Loveridge is a Dreamslinger, born with a genetic mutation that transports her to a magical realm while she sleeps. In much of the world, slingers are seen as dangerous, especially after the Great Outburst, caused by the Royal League of Dreamslingers, killed thousands - including Aria's mother. Since then, Aria's dad has become a leading expert on Dreamslinger Welfare, which means Aria knows better than most what it takes to keep society safe from her, and others like her - separation, identification, and most importantly, power suppression. So when the Royal League opens their Trials to Dreamslinger teenagers from around the world, Aria signs up to take them down from the inside.