Kill Joy (2023) is a young adult novella by Holly Jackson. It serves as the prequel to the A Good Girl’s Guide to Murder trilogy. The novel takes place over the course of one evening during which Pip and her friends play a murder-mystery role-playing game. Throughout the evening, Pip becomes increasingly invested in unraveling the mystery, setting the stage for events to come later in the series.

This guide refers to the 2023 Delacorte Press hardcover edition.

Content Warning: The source text and this guide discuss murder, death by suicide, and addiction.

Plot Summary

Kill Joy begins with a facsimile of an invitation to a murder-mystery game, addressed to Celia Bourne (played by Pippa “Pip” Fitz-Amobi, the protagonist of the text). Pip’s friend Connor Reynolds is hosting a murder-mystery party to celebrate the end of final exams. In the game, Pip will play the character of Celia, a young woman who is an orphan and the niece of the game’s murdered main character, Reginald Remy. Pip is hesitant to go to the game night because she is worried that she has still not decided on a topic for her senior capstone project, despite it being only the beginning of summer. Pip resolves to go to the party to try and have fun, although she views fun as a waste of time.

Pip and Zach arrive at Connor’s house. Connor, dressed as his character, Reginald’s butler, greets them. The rest of their friends are dressed up as their various characters: Ant Lowe will be playing Robert “Bobby” Remy, the eldest son of Reginald; Zach is Ralph Remy, the younger son; Lauren is Lizzie Remy, Ralph’s wife; and Pip’s best friend, Cara Ward, plays the cook. Connor takes their phones so that they can focus solely on the game. Connor tells them that they are home alone for the duration of the evening, but Pip thinks she hears something upstairs.

Connor tells them that they have all gathered to celebrate Reginald’s birthday, but the guest of honor has yet to arrive. Connor tells the players that they must go look for him, and Pip understands that this means that Reginald has been murdered and they are to find evidence of this. Pip goes upstairs and opens the door to Connor’s father’s study, which has a paper label on it stating that it is the library, for the purposes of the game. When Pip opens the door, she finds Connor’s older brother, Jamie, slumped over in a chair covered in what appears to be blood. Shaken at first, Pip then sees Jamie laughing and realizes that he is playing Reginald.

The others arrive, and Connor instructs them to go back downstairs now that they have discovered Reginald’s murder. Jamie appears as well, dressed now as an investigator, Inspector Howard Whey. As he begins explaining that it is their job to figure out who the killer is, Ant cries out that Sal Singh must have done it. This is an allusion to the real-life murder of their former classmate, Andie Bell, five years ago. The town largely believes that Sal, Andie’s boyfriend at the time, killed her, in large part because he died by suicide only a few days later. Pip thinks about how she knew Sal personally and how she still struggles to believe that he was guilty based on how kind he was to her when they knew each other.

Jamie redirects the players’ attention to the game and asks them to introduce themselves in character. He informs them that their characters all arrived the day before on the same boat from the mainland (there is only one boat per day) and that on the night of his birthday, Reginald died from a single stab wound to the heart. He tells the players that they need to learn their alibis now and instructs them to turn to the next page of their game booklets.

Pip learns that her alibi is that she was in bed taking a nap at the time of the murder. The players determine that there is a one-hour-and-15-minute window in which the murder could have taken place. When they share their alibis, it appears that no one has a strong enough alibi to exonerate them and that each had the opportunity to commit the crime. Jamie then informs them that they need to discuss motives and shares that he found the murder weapon, placing one of their kitchen knives on the table.

Everyone turns to Cara, the cook, accusingly, and she leads them to the kitchen, where they find the first clue, a note addressed to Cara’s character signed by “RR,” who turns out to be the eldest son, Bobby. Through reading the clue, Pip determines that the kitchen was left empty for a significant portion of the day, enough time for any one of the players to have stolen the knife. The doorbell interrupts her explanation, and Lauren screams.

Jamie tells Lauren to stop screaming—the pizza has arrived. While the others eat, Pip writes down notes about the case in her game notebook. She realizes that she is becoming increasingly engrossed in the mystery and wants to solve it. Jamie informs everyone that upon inspecting the crime scene, he has discovered that someone has stolen the contents of Reginald’s safe. Before Jamie can finish their next instructions, Pip is off to find the missing evidence, which she does in the living room in a pile of ripped-up paper strewn in the fireplace. She and Zach put the pieces back together, and the paper reveals that this is the second clue: Reginald’s last will and testament, dated only a week before his death.

Pip brings the will back to the others and reads it aloud. The Reginald wrote his son, Bobby, out of the will. As rounds of the game progress, with players accusing each other as instructed by the game booklet, the evening intensifies. Multiple unexpected and thrilling events interrupt the game, such as the crash of the shed door outside and Ant’s prank of pretending to go missing only to startle them all at the dining room window. Pip’s focus on the game intensifies as well, carefully going over each of the characters’ motives and opportunities to have committed the crime.

Pip worries momentarily that her character could be the murderer when she learns that Celia is a spy for the British government and is at the island on an assignment to investigate her uncle’s supposedly communist sympathies. Pip then learns that her character is not the murderer, and she feels immense relief at this revelation, turning her attention to figuring out the killer’s identity. She feels close to unraveling the mystery but feels that she is missing some crucial piece of information to fit everything together.

Her pursuit comes to a halt when the lights are cut off in the house and Jamie tells them that someone has to go downstairs to reset the fuse box. Pip volunteers, and while she’s downstairs, she discovers a final, secret clue that is meant just for her: Reginald received a fatal cancer diagnosis shortly before his death and paid off a doctor only a few weeks prior to keep this information a secret.

Pip feels that this knowledge is the final piece she needs and begins crafting her final theory alongside the other players. Jamie has each player share their final guess and saves Pip’s guess for last. When it is her turn, she presents her elaborate theory, accusing Zach’s character, Ralph, of being the murderer, but only because he was working alongside his father to frame Bobby for the murder. She also explains that Jamie’s character, Inspector Whey, was also in on the plot because Bobby murdered his partner during a drug bust of the gang that Bobby had gotten involved with due to his gambling habit. Pip points out that the inspector was already on the island, ready to investigate the murder, although he had not come on the one boat that visits the island each day with the other guests.

Pip’s friends are amazed at her ability to piece together the entire plot to craft an airtight explanation. Pip’s excitement is short-lived when Jamie reads out the game writers’ explanation: Bobby is the murderer. Incredulous, Pip argues that this theory is too easy and leaves too many plot holes, but Jamie insists that this is the given explanation. Pip grows angry, frustrated not only that she was wrong but also that she let herself become so invested in the fictional investigation.

Cara’s dad gives Pip a ride home. Cara and Zach lightly tease her about how invested she became in the game. Pip mulls over the explanation the game gave and how overly simplified it was. Mr. Ward asks Pip if she has chosen her topic for her senior capstone project, and as Pip begins to respond, Mr. Ward stops the car suddenly, claiming that he thought he saw someone, before continuing to drive. Pip sees Ravi Singh, Sal’s younger brother, walking away into the night. She begins thinking about how the accepted explanation that Sal must have killed Andie might be overly simplified as well. Pip watches Ravi walk away, her mind spinning as she says that she thinks she has finally settled on a project topic.