The Prisoner in the Square — Dorothy Quentin

House of tragedy...
As the storm gathered and broke about the old house, Mandy Browning knew she was facing the most sinister force that had ever entered her life, a growing peril that would demand all her resources of courage and cleverness.

With a sharp stab of fear she realized that she was alone in the house with a madwoman and a terribly endangered child. Had she been right to bring the little prisoner back to the house of tragedy? And where was Oliver? Why - why - wasn't he there to help her?