Crimson Nation

In 2005 two FBI agents uncover a disconcerting reality, the government was being taken over and run by vampires. That same year they end up being assassinated, orphaning their 6 year-old-son. Nearly nine years later the former deputy director of the FBI seeks out the agents' son and take him under her wing. She ends up training him. A few years later they and a small band of former government agents go up against the vampires.