Thirteen-year-old Matthew “Moose” Flanagan, the novel’s protagonist and first-person narrator, lives on Alcatraz Island with his sister, mother, and father, who is the associate warden of the Alcatraz prison. Tall for his age, Moose has a powerful throwing arm, which comes in useful in the story when he disarms a knife-wielding con with an expertly aimed baseball. Matthew deals with more pressures than do most boys his age since he worries constantly about his father, who he thinks is “too nice” to be a warden—especially of Alcatraz, one of the “roughest” prisons in the country. Accordingly, he begins to test himself, showing his courage by confronting dangerous adults who threaten his family, including the convict Indiana and the guard Darby Trixle. Added to this, his older sister Natalie has a developmental disorder that requires constant attention, and he devotes much of his time to both protecting her and trying to make her more independent. These latter efforts prove a source of friction with his mother, who sometimes feels he is pushing Natalie too hard to engage with the outside world. Moose’s worries come to a head when his family’s apartment burns down, for which he does not know whether to blame Natalie (and therefore himself, as he was supposed to be watching her) or some unknown person who may be targeting his father.