When ten-year-old Byron "Boon" Barnett boards a rocket-ship for a move to the Moon with his family (and his irritating robot, Jose Ignacio), he's expecting the time of his life in the lunar colony of Cosmopolis. What he's not expecting is a stellar disaster that'll demolish Cosmopolis before lunch. Boon insists he knows how to survive it, but people tend not to believe him about stuff. His parents have been lecturing him on the dividing line between using his imagination for fun and using it as an excuse for bad behavior. Suddenly it's the dividing line between life and death.