Content Warning: My Best Friend’s Exorcism references and depicts violence such as physical abuse and sexual assault, mental health conditions such as suicidal ideation, self-harm, underage drinking, underage drug use, anti-gay bias, racism, enslavement, animal death, and potentially nauseating imagery such as the use of tapeworms for dieting.

Chapter 1 uses third-person narration in the present tense. In 2008, 36-year-old Abby Rivers sees an online story about an exorcist—Christian Lemon (Brother Lemon)—dying in a car accident. She remembers how this exorcist helped when her best friend, Gretchen Lang, was possessed by a demon in high school.

Chapter 2 switches to the past tense. In 1982, middle-class nine-year-old Abby is in fourth grade and obsessed with the movie E.T. the Extra-Terrestrial. She’s planning an E.T.-themed birthday party at a roller rink, and invites her class, planning on impressing everyone with her skating. A few days later, a wealthy classmate named Margaret Middleton invites the class to her family’s polo plantation to ride horses on the same day as Abby’s party. The teacher reassures Abby that her classmates will have time to attend both parties.

Abby and her parents arrive early at the rink to set up E.