The Guardians of the Universe send the Third Army, an army of emotionless drones, to convert living creatures into soulless creatures like themselves. With Earth's Lanterns either dead, powerless, or on missions in deep space, the Green Lanterns, accompanied by an unexpected new human Green Lantern, prepare to confront the mad Guardians, but their desperate attempt to save all sentient life in the universe could unleash an even greater evil.