The mother of four daughters and an architect, who employs Rowan/Rachel at her family's residence, Heatherbrae House. Her meticulous care for family and work is evident through detailed instructions and surveillance measures.

Sandra's husband and the father of the Elincourt children, involved in architectural work. His complex family relationships and backstory play a significant role in the unfolding events.

One of the Elincourt daughters under Rachel's care, characterized by her dark hair and challenging demeanor. Her actions significantly impact the narrative.

A young Elincourt daughter with blond hair and blue eyes, who is often influenced by her sister Maddie. Her relationship with Rachel becomes more significant as the story progresses.

The youngest Elincourt child, an 18-month-old baby, who is also under Rachel's care during her time at Heatherbrae House.

The eldest Elincourt daughter, exhibiting a precocious and rebellious nature. She uses her knowledge of certain secrets to her advantage.

An employee at Heatherbrae House and Rachel's love interest during her stay there. He is characterized by his good looks and Scottish accent.

An employee of the Elincourt family, who spends much of her time caring for her father. Her initial coldness towards Rachel softens over time.

Rachel's mother, whose strained relationship with her daughter is explored through Rachel's reflections. Her absence marks a significant emotional background for Rachel.

The previous owner of Heatherbrae House, noted for his work in analytical chemistry and a tragic backstory involving his family. His presence is felt through the house's history and mysterious atmosphere.

The lawyer to whom Rachel writes, seeking to gain his representation in her legal case. His potential involvement represents hope and possible salvation for Rachel.