From audible.com:

The year is 3326. Nigel Sheldon, one of the founders of the Commonwealth, receives a visit from the Raiel - self-appointed guardians of the Void, the enigmatic construct at the core of the galaxy that threatens the existence of all that lives. The Raiel convince Nigel to participate in a desperate scheme to infiltrate the Void. Once inside, Nigel discovers that humans are not the only life-forms to have been sucked into the Void. The humans trapped there are afflicted by an alien species of biological mimics - the Fallers - that are intelligent but merciless killers. Yet these same aliens may hold the key to destroying the threat of the Void forever - if Nigel can uncover their secrets.

From audible.com:

The planet is isolated from the rest of the universe, unable to seek help as it's targeted by hostile aliens. Bienvenido's ruling authorities have slowly responded to this gradual infiltration, but they have no idea that a highly organized invasion is now under way, designed to wipe out all human life on the planet. All factions must work together to survive. Unfortunately, due to prejudice against enhanced Eliter humans and crippling technophobia, the parochial government won't collaborate.

Kysandra, known as the Warrior Angel, heads up the Eliter resistance. With their enhanced capabilities and technological know-how, they could avert disaster, but only if the authorities stop hunting them at every turn. Then, as both resistance and government are caught in a desperate race to save lives, the planet receives an unexpected visitor. As events escalate, petty power-plays, politics, and age-old prejudices may prove fatal. And as the more sophisticated hostiles can hijack a human body, humanity is undermined by spies within - wearing the faces of family and friends.