Content Warning: This section of the guide includes discussion of death, graphic violence, and suicidal ideation.

Monica’s mother, Louise Johnson, is not the same woman Abby talked to on the phone. Louise asks what Monica has “done this time” (229), explaining that her daughter has caused trouble since her teenage years. She describes Monica as “unstable,” revealing that they consulted many psychiatrists but that she never received a definitive diagnosis. Louise says that Monica is “a math genius” and that her high IQ makes her particularly dangerous (231). She reveals that in high school, Monica and her best friend, Sandy, argued over a boy. Shortly afterward, Sandy was murdered. Although Monica was the prime suspect, her guilt could not be proven.

Louise explains that Monica cut her parents out of her life after an argument three years earlier. The Johnsons disapproved of their daughter’s affair with her married math professor. Louise confirms that the professor’s name was Sam.

Abby reflects that Sam must have stayed with her for her money while having an affair with Monica. She guesses that Monica and Sam have been plotting together for years and that Sam lied about Janelle pulling out of the adoption. She reasons that they both worked to framed her, jointly spiking her food, planting the drugs, and killing Denise.