After a devastating loss to the alien Antaere, the forces of Earth have been driven back to the Solar System, to wait helplessly while the aliens muster enough strength to make one final push. 

Now the salvation of the Human race lies with Captain Zac Murphy and his natural REVs, the unforeseen byproducts of an experiment using super-enhanced Marines as the ultimate killing machines. With the human military now reduced to a shadow of its former self, the REV super-warriors must pull triple duty as they form an invincible defensive shield for the planet. And not only that, but they need to beat back the aliens, eliminating their threat once and for all. Only then will mankind have a future. If not, then we die.

This is the pivotal book in the series, the one where we find out if mankind will survive...or will we join the dust bin of history as just another extinct species? At the moment, our prospects don't look too good. And the key to our success is dependent on the secret work carried out by Dr. David Cross and his quest to develop a new kind of man...and woman. Here we're introduced to Sergeant Joanie Hollis, soon to become the first female REV. Her contributions to the survival of the species are nothing less than epic.