Moose Flanigan: A young boy who moved to Alcatraz because of his Dad's job and is over protective with his sister
Natalie Flanigan: Moose's "little sister" who is always ten but is older then Moose. She has a disorder that makes her act ten despite her age.
Dad: Moose's father who is one of the prison guards on Alcatraz.
Mom: Moose's mother, she now teaches daily piano lessons and she supported the father in going to Alcatraz.
Piper: The warden's daughter, also has a sassy attitude, and charges the kids at school to get their clothes washed by the convicts.
Warden: The head leader of Alcatraz, also the father of Piper.
Al Capone: A famous mob leader of the Chicago Mafia.
Theresa: A little girl who knows everything on Alcatraz. (she also lives on Alcatraz)
Annie: Another girl, who helps Theresa with stuff.