War Ravens (The Taken #1)

Eons ago their ancestors were taken from the Earth and forced into servitude. The unforgiving hidden masters ruled their lives and shaped their bodies until they became something ... Other. After a devastating rebellion that left the Hidden Ones shattered husks and their empire a wasteland, all but a few of the Taken are dead. Nothing will stop the warriors now for fulfilling the one dream their people have kept over the ages. The people that have only known war and deprivation for thousands of years are going home.

But is the Earth ready for them?

Erin is an overworked and underpaid cop when giant metal ships resembling ravens fill the sky sparking riots across the city. She isn't sure what is going on and doesn't have time to care as the situation spirals out of control. Who cares about aliens when the world is falling apart around you?