SKY ON FIRE continues the story that began in MONUMENT 14. It is told from two points of view by two brothers. Dean tells about what is happening to the kids left in the superstore while Alex tells the story of the kids who take off in the bus to look for help. Both groups of kids face horrible difficulties ranging from chemically deranged murders to gangs and to the fact that the air can kill some of them. It is 2024 and a series of disasters including a monster hailstorm and chemical weapons spills have devastated the area around Monument, Colorado. Fourteen kids on a school bus were driven into the superstore to take shelter from the storm. They ranged in age from seniors to kindergartners. Their bus driver takes off to try to find help and doesn't return. The chemical weapons have different effects on the children depending on their blood types. Type Os turn into "bloodthirsty monsters" if they breathe the air. Type ABs suffer from paranoid delusions. Type As blister and die. Type Bs have few symptoms but suffer from reproductive failure which Alex figures isn't that big a deal since they have much more immediate threats to their survival. When this story starts, the group has split in two with one group waiting for rescue in the superstore and the other group taking off in the school bus to try to get to Denver International Airport for help. The story was exciting. The events were chilling. It was interesting to read about the dynamics within the group and how desperate situations bring out the best or the worst in people. There wasn't a lot of character development here for most of the younger kids but it was still clear that they had all bonded together to survive. While this book is relatively short making it a good choice for middle graders, some of the themes which include sex and violence might make this book too intense for them. Many of the characters have to make very difficult choices in order to survive. I think the best audience for this title would be YA reluctant readers who are interested in post-apocalyptic stories and dystopias. To get the full effect of the story, readers must read MONUMENT 14 first.