I needed to get out of the car. I tried to identify who was underneath me. I realized that it was Aaron, and someone else was lying on top of me. I managed see that Aaron was unconscious. Then I saw the spurt of blood flowing over his face. My body heaved as Aaron gasped. I didn't know if the blood was his, but I knew I had to move. I pushed up with all of my might and felt the CIA agent roll off my legs freeing both me and Aaron. We were all soaked with blood, and suddenly I realized that I was looking at the stump of the agent's left arm. It was gushing blood and was severed just below his shoulder. Good-bye, Chicago is second in a series of three books dealing with Islamic terrorism. Chicago is the target of a terrorist group from Afghanistan. Our heroes track a shipment of radioactive bomb components to Chicago and discover that the bad guys are planning a three-bomb attack. Neutron bombs are planned to be exploded over Chicago from hot air balloons. Pete Simon and Aaron Colson hold our future in their hands.