Friendship and struggle
Because Austin and Robby endure the same struggles together, their friendship deepens, and they are more ready for the journey that the novel entails. They aren't happy about being bullied or beaten up, but ironically, the bad guys who attack them are defeated, and the friendship endures. The novel seems to be suggesting that friendship is so powerful that it can endure the worst moments of time. This is ironic, because friendship turns struggle into power, from a bad thing to a good thing.
The journey up and down
Because of the bullies, Austin and Robby have to ascend the building to get their skateboards. Then, they have to descend back into the building from above, and their unique location gives them access to the bosses room from above. This means that the bullies' attempt to make their lives worse and more inconvenient actually makes them better off. They defeat the bullies because they find a secret weapon, and their discovery of Plague 412E makes them able to survive the coming apocalypse.
The ironic weapon
The weapon known as Plague 412E is discovered on accident just moments before Austin and Robby are attacked for a second time by the mob of bullies. They are able to defeat the bullies because of a weapon they had no knowledge about only moments before, a weapon designed to harm them. What was designed for bad is used for good. Although the weapon saves them, it also puts them in serious danger, and they have to escape the plague that they set into motion.
The escape to silo
When Austin and Robby arrive at Shann's house, they realize that their journey is not ending; it's just beginning. They have to find safety by escaping to a silo. The plague is proven to be airborne, and they realize that their community is doomed. This realization is apocalyptic in tone, because they see that their entire world as they know it is coming to an end, and they don't expect many survivors. This irony is thematic, because it shows that everything could change in the blink of an eye.
New Eden
Ironically, the book ends in a place called Eden, which is famously a starting point, not a finishing point. Although the name of the silo community is paradisal, that doesn't spare them from the hellish reality that is taking place outside. This ironic name points the reader to consider what true paradise is. Is paradise the elimination of threats or promises? No, in this novel, paradise is a trustworthy community that bands together for survival and support.
