In this sci-fi thriller, Harper (Isabella Hoffman) is a reconnaissance agent from an alien civilization sent to Earth to study the planet and its inhabitants. Harper has taken over the body of a human being in order to not seem conspicuous, and has been performing tests to see if her mind control techniques will make it possible for her people to enslave the human race. But Harper has learned that most of the earthlings do not respond to her methods, and another three alien scouts -- Alpha, Bravo, and Charley -- are sent to see if the path can be cleared for a massive invasion of the planet three days hence. While Harpers new comrades show little concern or compassion for human beings, she has developed an understanding of humans during her six months on the planet and is no longer certain that taking over the planet is a good idea. The Advanced Guard also stars James Avery, Michael Weatherly, and Jeff Kober. ~ Mark Deming, All Movie Guide