Wren received something for her eighteenth birthday that she was fairly sure was one of a kind: sky-blue wings. But along with those wings comes the knowledge that her father had a surprisingly practical reason for abandoning her when she was eight. In his letter to her , delivered via talking raven , she learns that it’s up to her to save billions of humans and Winged Blue from a threat that’s on the horizon and closing in fast. She is to travel to the world of the Winged Blue thirteen days after her birthday , and before she leaves , an attractive winged young woman named Sia will be teaching her how to fly. Wren has to hope that her world’s prophecy is right , and that she is up for something even more challenging than growing up gay in a small town: saving two entire worlds from the Winged Red.