Humanity has been rendered infertile in a global event known as the Lost Spring, sparking a desperate race to develop artificial wombs to survive.

James Olsen is the maintenance supervisor at an artificial womb lab in Upstate New York, where they are on the brink of developing the first successful prototype. But on the eve of its creation, an asteroid projected to strike the moon breaks apart, sending massive fragments hurtling toward Earth. Though, their size is far less dangerous than what is hidden within them.

After a cluster of asteroid fragments strikes near his lab, James is thrust into a fight for his life—a life that at its start seemed cold and futureless, a slow march toward extinction full of only pain and suffering. But as he and Ashley, one of the lab’s lead scientists, find themselves adrift with two artificial wombs, watching the babies inside them grow, the first in over twenty-five years, everything changes.

However, nothing can change the two thousand miles that lay between them and the haven in Colorado they are trying to reach. And the threat from the fragments, as well as those originating closer to home, will be hunting them every step of the way.