Billy has been removed, by court order, from the loving protection of his father and grandmother, and placed with his older sister and younger brother in a boarding home run by Mrs. Blair, an over-religious zealot.
Billy struggles to find his grandmother's teachings of love and understanding in the Blair household, but is constantly thwarted by Mrs. Blair's preaching's that the Devil lives in him, and that God will send him to Hell. He turns his trust and friendship to Bax, a neighbor-boy, and together, they play out many happenings.
In the meantime, Billy continues with his efforts to isolate himself from Mrs. Blair, and to gain his independence.