Under Fire (Brothers in Arms: Retribution)

An experiment gone wrong unleashes the most elite killers on the planet 

When an unstable patient opens fire on Ava Whitman's lab, only a bulletproof window and agent Max Duvall stand between her and certain death. Max vows to prevent Tempest—the covert ops agency behind the shooting—from killing the one witness left standing: Ava. But a victim of a brainwashing attempt, Max is battling his own demons. How can a man who has been programmed to become a mindless, soulless killer keep the emerald-eyed beauty safe? Now on the run and running out of time, Max has to use every ounce of strength to ignore his deadly tendencies. And every bit of willpower to not give in to his desire for Ava.