Captain Arthur Keller is Helen Keller's father. Arthur is his first name. In The Miracle Worker, he is described as "a hearty gentleman in his forties with chin whiskers." He also wears spectacles. He is a newspaper editor and has a newspaper on his person throughout the play. He is doubtful that anyone can help his young daughter, Helen. She had become deaf and blind as a baby due to an illness. When Miss Sullivan arrives in Alabama to be Helen's teacher, Captain Keller is doubtful that the woman will be able to do much to help.
Captain Keller is significantly older than Helen's mother, Kate Keller. In the script, he is most commonly referred to as "Keller," though sometimes Aunt Ev calls him by his first name, Arthur. His wife, Kate, calls him "captain" in the play.