Lisey is the 50-year-old widow of celebrated author Scott Landon. Outwardly composed, she manages her eccentric family and fends off intrusive fans while privately suppressing memories of her husband's traumatic past. She serves as the primary caretaker for her sister Amanda. Resourceful and deeply loyal, Lisey slowly faces the supernatural elements surrounding Scott's life as external threats force her to act.

Scott is a deceased Pulitzer Prize-winning author who left behind a vast collection of unpublished material and a dedicated fan base. He suffered a highly traumatic childhood marked by violence and mental illness, which he managed through storytelling and creating elaborate puzzles called bools. His connection to an alternate dimension profoundly influences his art and his marriage.

An obsessed fan of Scott Landon's writing who attempts to forcefully extract the author's unpublished manuscripts from Lisey. He uses extreme violence, psychological terror, and intimidation tactics to get what he wants. His intense fixation on Scott's literary legacy strips him of basic human empathy, making him a highly dangerous adversary.

Amanda is Lisey's 59-year-old older sister who experiences severe mental health episodes, including periods of deep catatonia and self-harm. She requires regular care and supervision from her siblings. Despite her vulnerabilities, she possesses an unusual sensitivity to the supernatural elements connected to Scott.

An academic from the University of Pittsburgh who aggressively seeks access to Scott's unpublished papers. His sense of entitlement over the late author's work blinds him to the emotional toll his demands take on Lisey, leading him to make highly irresponsible choices.

One of Lisey's sisters who lives nearby. She actively assists in managing Amanda's frequent psychiatric emergencies, sharing the logistical burden of care with Lisey while offering emotional support to the family.

Lisey's sister based in Boston. She remains in close contact with her family to help coordinate care and support during Amanda's recurring crises.

Scott's deceased older brother who suffered from severe mental illness as a child. He protected Scott from their father's violence when possible and created the first bools as a coping mechanism for them both.

Scott and Paul's father. He raised his sons on a rural farm while battling intense mental instability and abusive outbursts that he referred to as the bad-gunky.

A massive, terrifying entity residing in the alternate dimension of Boo'ya Moon. Described as having an endless, piebald side, it represents the physical manifestation of horror and trauma that threatens to consume visitors.

A disturbed young man who shoots Scott at a public event in Nashville, creating a lasting traumatic memory for Lisey.

A doctor at Greenlawn in Auburn who treats Amanda. He previously made a private arrangement with Scott to ensure Amanda would always have care if her family ever needed assistance.

A professor who attends the 1988 library groundbreaking ceremony in Tennessee and introduces Scott to a graduate student shortly before violence erupts.

A graduate student at the University of Tennessee who receives public credit for stopping Scott's attacker, despite Lisey being the one who actually intervened to save her husband.

A local sheriff's deputy assigned to monitor Lisey's property and ensure her safety from ongoing harassment.

The attending physician in Bowling Green who treats Scott when he succumbs to a sudden, mysterious illness while traveling.

The head of the English Department at Bowling Green who hosts Scott for his final speaking engagement before his sudden collapse.

The Head of Personnel at Gypsum USA who checks on Sparky Landon after he misses several days of work without explanation.

A sheriff's deputy dispatched to keep watch near Lisey's home after she begins receiving violent threats over the phone.

A sheriff's deputy who initially documents Lisey's harassment complaints and dispatches officers to monitor her home.

A librarian from the University of Maine who helps box up Scott's massive collection of literary magazines and materials.