The first act of The Miracle Worker establishes the setting and characters of the play, beginning with the infant Helen’s recovery from scarlet fever. The play opens on the Keller Home in Tuscumbia, Alabama, in the year 1882. Helen’s parents, Captain Keller and Kate Keller, look in their child’s crib with the family doctor as he examines Helen. To his surprise and her parents’ relief, the doctor says that Helen will survive. Captain Keller sees the doctor out, and Kate is left alone with Helen. Kate speaks to and waves at Helen but receives no response from her young daughter. With horror, Kate realizes Helen can no longer see or hear.

When Helen is just recovering from scarlet fever, Captain Keller brags that Helen’s survival didn’t surprise him in the least. He tells the doctor, “the child’s a Keller, she has a constitution of a goat. She’ll outlive [them] all” (5). Five years later Captain Keller changes his tone, saying that he’s “stopped believing in wonders” (10).

Helen, now six-and-a-half, is playing with the servant’s children, Martha and Percy. As they speak, Helen fumbles her fingers into their mouths and then touches her own.