Max knew that a bunk bed was the perfect structure to use when building an indoor fort. First of all, bunk beds have a roof, and a roof is essential if you’re going to have an observation tower. And you need an observation tower if you’re going to spot invading armies before they breach your walls and overtake your kingdom. Anyone without a bunk bed would have a much harder time maintaining a security perimeter, and if you can’t do that you don’t stand a chance.

Max had just done a quick survey of the area surrounding his bunk kingdom and was now down on the lower bunk, where he could be unseen and unknown. For a while, he thought about what his science teacher had been talking about earlier that day—that someday the sun would die. Mr. Malhotra had sensed that the mood in the class was darkening, that he’d scared his third graders, and had tried to brighten things: “What am I talking about? I’m being such a downer. Don’t worry about the sun dying! You and everyone you know will be long gone by then!”

It was a very strange time in Max’s life. The day before, his sister had tried, by proxy, to kill him. Her tobacco-chewing friends had chased him into his snow fort, and at the moment when he felt safest, in the cool white hollow, they had jumped on the roof, burying him. His sister had done nothing to help, and then had driven off with them, and to punish her, because she was no longer his sister, he’d doused her room with water. Buckets and buckets he’d emptied everywhere, in a furious, joyous process. It had been great, and felt so right, until his mother came home and found what he’d done. She was mad, Claire was mad, and so, tonight, the only person in the house who seemed to like him was his mom’s chinless boyfriend, Gary, and even thinking that sent a shudder through him.

Max, tired of thinking in his brain, decided to think on paper, and so retrieved his journal from under the bed. His father had given him the journal short...