The Mystery Guest is Nita Prose’s second novel in her Molly the Maid series. In this novel, the famous mystery writer J.D. Grimthorpe dies in the Regency Grand Hotel’s tearoom just as he is about to reveal a secret to his adoring public. Molly, the Head Maid at the hotel, must solve the murder in order to save the hotel’s reputation and prevent herself or her staff from being arrested. Doing so means revisiting a painful past and admitting that she and her beloved Gran had dealings with Grimthorpe years ago.

An experienced editor and a writer of stories that fall into the “cozy mystery” genre, Nita Prose has penned three novels as of 2024 for her Molly the Maid series. Her inspiration for her first novel, The Maid, is based on a chance encounter with a maid in a London hotel. The novel became a number-one New York Times bestseller and has since been sold in 40 different countries in addition to winning the Ned Kelly Award for International Crime Fiction, the Barry Award for Best First Mystery, and the Anthony Award for Best First Novel.

This guide refers to the 2023 Ballantine Books e-book edition.

Content Warning: This novel and this guide contain references to alcohol addiction and sexual violence.

Plot Summary

Throughout the novel, the chapters alternate between the primary narrative and a series of flashbacks. The novel begins with a story that Molly’s gran tells about a maid who is blamed for stealing a silver spoon. The maid is disgraced and dismissed, and years later, a mummified rat is found under the floorboards along with the missing spoon.

The narrative shifts to the present moment. Molly is proud to be the Head Maid at the Regency Grand Hotel. Although her grandmother has passed away, she still hears the memory of Gran’s voice. This morning, the famous mystery writer J.D. Grimthorpe suddenly died in front of a crowd of reporters and the Ladies Auxiliary Mystery Book Society (LAMBS). He put honey in his tea, drank it, and died, falling onto a Maid-in-Training named Lily Finch. Lily is now petrified as she waits with Molly in the office of the manager, Mr. Snow. As she waits, Molly remembers telling Mr. Preston the doorman that Room 404 was such a mess that it even had an open jar of peanut butter with a spoon stuck in it. She also noted that Serena Sharpe, Mr. Grimthorpe’s assistant, got him to sign books for the employees. Molly was nervous to see the writer again after working for him years ago, but he did not remember her.

Molly also recalls a disastrous meeting with her school principal years ago, who wanted to hold her back a year for being a social failure despite her excellent grades. Gran took Molly out of school and had her work alongside her at the Grimthorpe mansion. On her first day, Molly was so overjoyed by a Fabergé egg that she tried to clean it. Mrs. Grimthorpe was furious because Molly’s cleaning destroyed the patina, rendering the egg worthless.

Now, in Mr. Snow’s office, Detective Stark (who accused Molly of murder in the previous novel, The Maid) reluctantly agrees to let Molly walk her through the crime scene. Molly notes that the honeypot and spoon are missing from the teacart. Mr. Snow, along with Molly and her coworker, Angela, and Mr. Grimthorpe’s assistant, Serena, go to the hotel lobby and look through a box of Grimthorpe’s belongings. Molly sees Cheryl and Lily cleaning in the lobby when they shouldn’t be. The fire alarm goes off, and after the evacuation ends, the box is gone.

Angela lies to the LAMBS and tells them that Molly is an undercover agent. Molly learns that there is infighting between them; a woman named Beulah claims to be Grimthorpe’s unofficial biographer. The ladies’ comments make Molly remember that Gran once helped Mr. Grimthorpe to detox from alcohol. Gran said she forgave him for his poor behavior during that time. Molly’s memories also reveal that the now-famous plot twist in Grimthorpe’s most famous novel came from the young Molly’s suggestion.

In the present, Detective Stark reveals that antifreeze was the poison used to kill Grimthorpe. Walking back to work, Molly sees Mr. Preston in a pawn shop, selling a rare first edition of Grimthorpe’s first book, The Maid in the Mansion. She remembers another time she felt betrayed: when she let a young, twitchy, and pock-marked woman into their apartment. The woman claimed to know her gran and turned out to be Molly’s mother. She tricked young Molly and stole their envelope of rent money. The landlord turned off their electricity in retaliation.

Now, Molly feels betrayed by Mr. Preston and angrily accuses him of stealing the book. He tells her that he was given the book when he was the gatekeeper at the Grimthorpe mansion. He remembers Molly as a little girl and says that her gran suffered horrible treatment there. Molly is horrified by her mistaken assumption and asks for forgiveness. Molly remembers that Mr. Preston used to date Gran and loaned her enough money to replace the stolen rent money.

Angela shows Mr. Preston and Molly a website on which someone is selling the items that Mr. Grimthorpe left at the hotel, including the contents of the missing box. One of the books is signed to Lily. Molly brings Lily to the hotel’s Social restaurant to see the website. Lily admits that Cheryl forced her to pull the alarm. Cheryl wanted to steal the box, and she also forced Lily to relinquish her tips. Cheryl confesses to her misdeeds and tries to bribe the others to stay quiet.

Molly recalls finding Mr. Grimthorpe downstairs, threatening Gran and trying to force himself on her. He stopped when Molly intervened. When Gran refused to stop working at the mansion, Molly pretended to steal the Fabergé egg so that Gran would be fired and would therefore be safe from Mr. Grimthorpe.

In the present moment, Cheryl admits her wrongdoing to Mr. Snow but defends her actions by blaming the low wages. She insists to Detective Stark that there was no honeypot or spoon but does admit to selling the rest of the items to one buyer with a P.O. box. When she says that the Moleskine notebook has only nonsense and doodles, Molly recalls details from her time in the mansion and realizes that Grimthorpe never wrote any of his books. Detective Stark realizes that she has underestimated Molly and takes her to Grimthorpe mansion to investigate further. They find the secretary’s office and a photo that shows the secretary with her child, Serena Sharpe. Serena finds them in her office and confesses that she had a contract in which Grimthorpe would announce her mother as the true writer of his novels and would then compensate Serena, but she couldn’t divulge anything before his announcement. This means that he was better off to her alive. As they drink tea, the sound of spoons in china cups tells Molly who the killer is.

Detective Stark, Molly, and Mr. Snow go to Beulah’s room in the hotel. It is a mess, and they find Grimthorpe’s Moleskine along with Beulah’s journal, which holds a record of years of rejections from Grimthorpe. A restaurant spoon and the poisoned honeypot are both in a satin-lined box in the bedside drawer. Later, in the tearoom, they trick Beulah into revealing that she knows about Grimthorpe’s preference for honey. She flies into a rage when they confront her about the poisoned honeypot in her room. At Detective Stark’s request, Molly explains that she knew something was wrong with the spoons on the day of the murder. The sound of the tearoom’s silver should have tinkled, but it clanked like because he was using the restaurant’s heavier cutlery—the spoon that Molly saw in Beulah’s open peanut butter jar the day before. Stark offers Molly a job, and she has a small identity crisis as she wonders what her true life purpose is.

A week later, the tearoom is again set for a press conference about Grimthorpe. Serena announces that Grimthorpe was a fraud, and his lawyers are awarding the titles and royalties to the rightful writer, her mother. Beulah confesses to finding out about Grimthorpe’s deception from a previous maid. She had written two biographies—one exposing the truth and one upholding his reputation—and tried to give Grimthorpe a choice of which would be published, but he rejected her entirely, prompting her to plan his murder. Stark reiterates her offer to Molly, tempting her with a uniform and a badge.

Mr. Preston tells Molly that he is her grandfather and that because he was poor, her gran’s rich family disowned her when she fell in love with him. He tried to help Gran, but she shut him out, got a job as a maid, and raised her child herself. It wasn’t until Mr. Preston was married that his wife was able to befriend Gran and offer help that she accepted. Juan Manuel comes home, and while Mr. Preston tells him all that’s happened, Molly feels the presence of her gran in the room.