Tag Reider's life was supposed to be simple after his retirement of 21 years in the Military Intelligence Service. But his past comes back to haunt him. A cave that Tag discovers in Cimarron, New Mexico, while a teenager working on a ranch, and plans to revisit, becomes the focal point and hideout for a cell of terrorists. They are out to spread deadly HCN gas over a group of military and CIA's top officials. But first they must eliminate Tag; he is the only other person who knows the location of the cave. After an attempt on his life by the terrorists, Tag gets involved with the CIA, who uses him on a temporary basis for this assignment. He quickly learns he has to become the hunter, not the hunted. Along the way Tag discovers that his friends and the government aren't always what they appear to be. Tag only wants to keep his wife, his new business partner, and his family out of danger while trying to stop the terrorists from spreading their deadly gas. He must accomplish this difficult feat while his own government is trying to prosecute him.