It's 1936, and Matthew 'Moose' Flanagan lives on Alcatraz Island. No, really. His father's just been promoted to deputy warden - so Moose, his mom and his autistic sixteen-year-old sister Natalie are expecting to enjoy some new benefits, even if everyone says his dad's too nice for the job. The last thing they expect is for their apartment to burn down on his second day. The tight-knit community of prison guards, their wives and their children are a mixture of welcoming and accusing - even the nicest people (heck, even Moose's mom) think Natalie probably had something to do with it - but Moose is sure she didn't. Nat's not dangerous, she's just...different. Determined to prove his sister innocent, Moose and his gang of fellow 'inmate' children must work quickly to find out just who started the fire - and why. But what they aren't expecting is a note from an old 'friend' of theirs: Alcatraz's 'star boarder' and the most famous gangster in America - maybe even the world.