The narrator, Grace Bernard, addresses the reader directly while writing from Limehouse prison. She’s been in prison for 14 months, and her cellmate, Kelly, is thrilled to be rooming with the “Morton murderer,” though Grace professes to be innocent of this crime. To ameliorate her boredom, Grace decides to write her story, certain it will become a bestseller. While she is innocent of the “grubby” crime of which she’s accused, she proclaims instead that she killed six members of her own family, without regret, by age 28.

Four years earlier, Grace steps off the plane near Puerto Banús in Marbella, Spain. Trying to avoid attention, she’s dressed plainly but catches the eye of a man named Amir. He works in nightclubs and offers her the use of one of his cars for her trip. She decides to take him up on the offer and gets his number before leaving the airport. Two hours later, Grace arrives at her rental and feels “woefully unprepared” to murder her grandparents, part of her plan to avenge her mother. Kathleen and Jeremy Artemis are the racist, bigoted, “disposable” parents of Simon Artemis, Grace’s father. After Grace’s mother Marie died, Grace lived with Marie’s friend, Helene, for a short while.