It’s been forty-three years since the Animal Plague forced everyone to move behind the safety of The Wall. Every animal on the planet was effected by the plague, causing them to turn viscious and kill anyone that got in their path. People still have nightmares and are afraid to even look at pictures of animals.Space is definitely a problem since the construction of The Wall. Only about a third of the planet is available for living space since everything outside The Wall is dead from the poison gas used to kill the animals and their habitats. Every available space is covered with concrete to make room for people. There isn’t any “real” food anymore since animals don’t exist and there isn’t any place for food to grow. People have to live on top of each other and those unfortunate enough to live on the lower levels have to battle the mold that grows everywhere because of the moisture and lack of sunlight. Life is dreary in the Shadows (the lower levels).Mika is a good kid, but He has been having a tough time lately though because he can’t get over the fact that his twin sister, Ellie, has disappeared. It’s been a year and everyone thinks she is dead - except Mika. He refuses to believe Ellie is gone. Mika has even more to think about when the government introduces a new game and fitness program in the schools. He has an unexplainable distrust of anything to do with the Fit For Life program, but when he learns that participating in the games might lead him to Ellie, he puts everything he has into winning.Emma Clayton does a great job of creating this post-apolcalyptic world for the reader. Science Fiction elements like Pod Fighters, space travel, and mental telepathy quickly draw the reader into the story. Mika is a loveable character and you’ll be on the edge of your seat as he and his gaming partner, Audrey, navigate their way through a sinister plan cooked up by an evil government. The ending definitely leaves room for a sequel.