It is 1872.

Annie Miller and the valiant members of the Peregrine Estate did all they could in Chicago to try and stop the Society of Prometheus from unleashing their terrible gods—The Nine—into our world. While they managed to save Carson Ptolemy from the occult society's ritualistic sacrifice, they failed to stop the ritual entirely. And thus, the ritual half-completed, an unknowable celestial body has set itself over the Sun, casting it into perpetual eclipse, throwing the world deeper into the shuddering cold and blackness of an unending, pestilential winter.

The sunless world brings to bear the great and terrible armies of The Red Kingdom, the hidden body of vampires who have decided that the eclipse is heralding their time to rise in full force and conqueror. The kingdom's sovereign monarch, and master of all vampires, Kristian, brings all his strength to bear out of the Astolat Mountain range in Colorado, beginning a war between humanity and vampires.

Annie and Carson, their lives now fully knotted together as members of the Peregrine Society and dear friends, work together with their allies to strike back against the vampiric horde, all while striving to set the world right in an epic third entry in C.S. Humble's Amid the Vastness of All Else Saga.