An illness cursing the land forces seventeen-year-old Vega, the Last Astronomer, to venture across the wilderness to discover the stars message that will save her people. "Vega is forbidden by her mother from leaving the safety of the valley: unknown threats await in the wilds beyond. But after her mother dies, and Vega sees the fabled twin stars in the sky, it's an omen she can no longer ignore. Leaving the valley turns out to be much more terrifying...

Just before spending her sixteenth summer on Cape Cod, Sarah's boyfriend breaks up with her and, as a scientist whose focus is on winning a scholarship through her study of a comet, she designs an experiment to become more like her older sister to see if she, too, can be popular.