"Arcadia’s defense corps is mobilized to defend against what first appears to be a routine assault, one of the many that the community repulses from paramilitary forces every year. But as sensors report a breach in the perimeter wall, even eighty-year-old Rachel Leopold shoulders a weapon and reports for duty. It's a distraction from her urgent research: to save the world from the horrors of climate change. Rachel is in a race against time as she...