Mary Maloney is the protagonist of the story. She is six months pregnant, a homemaker, and the wife of Patrick Maloney, a police detective. Mary is pleasant, quiet, devoted to what she sees as her marital duties, and competent in the domestic arts. She is well regarded by her community and by members of the police force where Patrick works.

At the opening of the narrative, she is a contented spouse, excited about her pregnancy and devoted to her husband. She displays great patience when Patrick’s arrival isn’t quite what she has come to expect, but when Patrick abruptly and callously reveals that he is leaving her, Mary becomes violent for a single instant that proves fatal for Patrick.

Mary’s capacity for violence comes as a surprise to her. In the aftermath of her crime, determined to protect her unborn child, Mary begins to utilize skills she didn’t know she possessed. In her interactions with the other characters, she proves to be clever, deceitful, and calculating as the story culminates in one final act of masterful manipulation.