A sardonic septuagenarian grandmother and her video game designer granddaughter become a pair of unlikely sleuths in this debut cozy mystery from Kelly Mullen. When a swanky charity auction turns deadly and a winter storm traps everyone inside the mansion, Mimi and Addie team up to find out who the culprit is.

I enjoyed this cozy locked room mystery! As a Michigan girl, I loved the wintry setting on Mackinac Island, which added a unique extra layer to the isolated feeling. The characters are a lot of fun, especially Mimi with her Gibson martinis, Pall Malls, and her snowmobile named Joan Rivers. I hope we get to see more adventures for Mimi and Addie in the future! Perfect for fans of Knives Out, Clue, and Only Murders in the Building.

Many thanks to NetGalley and Penguin Group Dutton for providing me an advance copy of this book.

This cozy-ish mystery is charming, entertaining, and clever. Set in an over the top, isolated mansion that serves as the locked room, with Mimi, a prickly older woman with a secret, and Addie, her granddaughter and the creator of a murder investigation game, as the main characters and investigators, this has elements of cozy and traditional mysteries with a fresh, modern voice.

Such a well paced and suspenseful book! The twists were believable and not predictable.
It had excellent writing and a fascinating plot.
This Is Not a Game by Kelly Mullen is a book which kept me thoroughly engaged from beginning to end.

Unfortunately I DNF this around the 20% mark. Couldn’t get into the story or relate to the characters.

This was a fun and clever locked room/snowed in murder mystery involving a grandmother-granddaughter duo who trying to figure out what is going on when the escape room party they were blackmailed into attending on a remote Mackinac Island, Michigan estate turns deadly. I loved the dynamics between the two main characters and the gaming references. While a bit slow to start for me in the beginning, once I got invested I couldn't wait to see how things were going to end! Highly recommended for cozy mystery fans or books like Murder at Gulls nest by Jess Kidd. Many thanks to NetGalley and the publisher for an early digital copy and @prhaudio for a complimentary ALC in exchange for my honest review.

4.25

As a mystery lover, I have several in the pile and opted, as is typical of me, for the British historical mystery first over this modern American one. I shouldn’t have been so glib.

This is a classic manor-house, stranded-amongst-a-murderer whodunnit, but with a modern twist. The house is fascinating with a mind-blowing history, and because it is so over the top, just like its owners, that allows the story to absorb most things that one might would question.

Mimi is 77, living on the automobile-free island of Mackinac, and well off, but nothing like her extravagant neighbor. She is a little prickly. When Mimi receives a an invitation to a party, accompanied with a blackmail letter outlining something she did in her past, she realizes she has to go and it is going to cost her. She calls on her only and closest living relative, her granddaughter Addie, who lives in Chicago, has been somewhat estranged from her grandmother ever since Mimi unapologetically shared her disapproval of Addie’s then boyfriend Brian. However, if Mimi is going to spend much of Addie’s inheritance on blackmail masquerading as a charity auction, she wants Addie’s support and to be honest, in theory, with her about her suspicious past.

Addie and is going through a crisis having been metaphorically stabbed in the back by her former fiancé and partner after designing a murder mystery video game that is now worth millions. His cunning meant that he manipulated Addie and took full credit without any recourse. She’s beat down and low on self esteem.

I love the idea, but can’t quite imagine this game in our modern world. It seems like something from the 80s or 90s. Then I remember Minecraft, which is a menagerie of pixels and blocks with simple movements. Anyway, when the hostess of the so-called party is murdered, the two team up to solve the mystery using Addie’s encyclopedic knowledge of murder mysteries and solving them and Mimi’s brazen, unapologetic attitude.

I recognized several things that have annoyed me in other books, but only a few parts that didn’t grab me. This was easy somewhat easy to follow but hard to solve. All in all, a fun read with an interesting trip through a fascinating house and a backstory where you don’t know who is on what side. Mimi and Addie deserve their glory and I hope she really rubbed it in her fiancé‘s face.

Thank you to Kelly Mullen, NetGalley, and Penguin Group Dutton for providing me with a free advanced copy of this book for my unbiased review.

#ThisisNotaGame #NetGalley #murdermystery #whodunnit

(Actual: 3.5⭐, rounded up) A quick & cozy mystery read, I really enjoyed this book! Definitely worth picking up for the propulsive story; all the vibrant, eccentric characters we join on this journey, main and secondary/ensemble alike, all also worthy of being suspicious of until the very end (+ dual POVs, yay!); the organic & flowy quality found in both Mullen's style of writing dialogue and in her pacing of the whodunnit plot.... there's a lot to like about and take away from this book imo, and I think it's also a very easy/accessible read for a wide audience range. Perfect for when you want something fun, something that makes you think and want to solve puzzles too, and to all those who love cozy mysteries!

Amateur sleuths, assemble! You have a whodunnit to solve... and this one is top tier.

When Mimi was buying her sourdough, I thought for sure we were in for a slow-paced mystery, but I was pleasantly surprised by how quickly the story got going.

The relationship between Mimi and Addie is adorable and very entertaining. The guests/suspects were all very interesting, and the reason they were all invited to this party will surprise you.

4.5*

I truly enjoy running across a good, locked room (or house) murder mystery and this one certainly met that mark. Addie and her grandmother, Mimi, are invited to an auction at a local socialite’s manor. The antics of the murder mystery begin, after the auction has concluded and the socialite is found dead moments after. There is a powerful snowstorm happening outside, so no one is able to leave and thus the mystery begins to play out.

I enjoy the dynamic between Addie and her grandmother, even though it seems their relationship has been strained for some time. I also enjoy the aspect that Addie is a mystery/ crime game creator and since no one else in the house has much experience solving mysteries. Quite a few personal secrets are revealed, and relationships are strained and tested.

Let me start by saying, I don’t know if this is a completely uniquely woven story, but I do think it was well crafted and fun to try and figure out. I also found it to be a lot of fun and the author did a great job with building the suspense and keeping the solution from being too easily solved.

This IS Not a Game is a debut novel by Kelly Mullen. It is a locked room mystery. Mimi is a widow and lives on Mackinac Island - there are no cars on the island. She likes her Gibsons served with three onions. She is the type of quirky elderly character that makes mysteries worth reading. She is invited to an event at the Grand Hotel, so Mimi invites her granddaughter, Addie, to join her. Addie invented a videogame with her fiance, but now she has been dumped and her fiance is cutting her out of their videogame as well. And, during a storm and loss of power, a socialite is murdered at the hotel. Mimi and Addie begin to investigate. I like these two women, although Mimi is definitely the better defined character. I'd love for this to be the first in a series of mysteries for this duo so we can see more character development for Addie. This is 3.5 star read for this cozy locked room mystery. Thank you to Net Galley and Dutton for my advance reader copy.

When Mimi is invited to a charity auction being held by a socialite who has the power to blackmail her, she invites her granddaughter Addie to attend the event with her. Addie, still recovering from a breakup that’s both professional and emotional, thinks the auction will be a pleasant distraction. While it in indeed a distraction, it soon proves to be anything but pleasant. A massive storm traps all of the guests inside the mansion – and then the hostess’s body is found. Mimi loves puzzles and Addie is a successful game designer, so they put their heads together to solve what turns out to be more than one murder.

This is the author’s first novel, and I enjoyed it. A snowstorm on Mackinac Island marooning a dozen people in an old mansion is the perfect setting for this locked-room mystery. Featuring a grandmother and granddaughter sleuthing team made it even better, and after I got into the story, it was hard to put down.

I liked Mimi and Addie, and appreciated that Addie gained more confidence in her abilities as the book progressed, giving her the… courage? to deal with her professional life in a most satisfying manner. I wasn’t so sure about the other major characters. They all had secrets (the reason they were invited to the auction in the first place), and they all were two-faced as well, being pleasant and cooperative one moment, then turning nasty and contrary the next.

Everyone was a suspect in the murders, and more than once, I thought I’d nailed the killer, only to have that person turn out to be the next victim. As the pool of potential killers grew smaller, it actually got harder to figure out who the culprit might be, but I figured it out just before it was revealed in the book.

There’s no indication that this is the beginning of a new series, but I hope it is. I’d like to spend more time with Mimi and Addie, and see where Addie’s professional life goes from here.

This is a fun locked room-style mystery featuring a grandmother-granddaughter team of sleuths. Mimi is fiesty with a dark secret and Addie is a mystery video game creator reeling from a breakup. At a very wealthy socialite’s auction, people begin to die and the secrets of all those in attendance begin unraveling. This book is full of twists and turns and secret passages. I enjoyed the mystery and the way the characters take us through their process. The dialogue was good and had some good humor. Overall, I enjoyed this and while it won’t be an all time favorite, I think others will enjoy it as well!

This was absolutely a cosy (as cosy as murder mysteries can get!) little story, spanning generations and bringing family members together. I would say that everything was there for a cohesive story that all comes together in the end, which is why my rating sits comfortably in the middle of the three star mark.
I liked the dual perspectives between our main characters, Addie and Mimi. Their relationship was tumultuous, and they came to odds sometimes but you could really see their connection, no matter how strained it could become.
There is an ensemble cast, and even the best books can struggle with getting each of their characters a suitable amount of description and characterisation. We get to know most of this ensemble to a degree, but I think some of the plot beats could’ve been harder hitting if we’d spent some more time with some of the minor characters.
I think the author did a great job of placing suspicion on each character, so much that I caught myself wondering if one of our POV characters actually had something to do with it! I had my suspicions, but I did managed to be surprised at times.

A cozy locked room mystery, set in a sprawling mansion in the middle of a winter storm. Our unlikely detective duo consists of Mimi, a blunt widow with a secret, and her granddaughter Addie, a video game developer trying to get over a recent breakup. My favourite parts of this were the setting of Mackinac Island and the mansion with its never ending secret passage ways. The video game Addie created, Murderspace, was also a really cool element and I totally wish it was a real thing.

But I think there was just something missing to make me love this one. I felt the chemistry was lacking between Addie and Mimi and it was a bit slower than my typical mystery novel. Also the subplot of Addie’s failed romance with Brian felt unnecessary.

THIS IS NOT A GAME by Kelly Mullen

Pub date: April 8th, 2025
Publisher: Dutton
Rating: 3 / 5


Who doesn't love a bit of blackmail with your murder?

Rosemary MacLaine, or Mimi to her granddaughter Addie, is being blackmailed. The deal? Attend socialite Jane Ireland's weekend charity auction... or else. Mimi abhors Jane, but with no other options, calls on Addie to join her for the weekend. Addie is in a messy legal battle with her ex-fiancé who is locking her out of a successful business deal, but both women's issues are soon overshadowed when Jane is murdered at her own party. Everyone's a suspect, and it seems the killer isn't stopping with Jane.

THIS IS NOT A GAME is a debut whodunnit mystery underscored by a charming family relationship. Mimi and Addie are the dual narrators and their dynamic is one of the best parts of the story. Mimi is a sharp, Gibson-loving old lady and Addie is a creative murder video game developer. While the book for the most part delivers a cozy, locked-room whodunnit, the ensemble characters and plot progression made it difficult to be fully immersed in the story. The ensemble characters did not have much personality or development. Rather, their existence in the story felt more like checkpoints to get to the next misdirection. The final reveal just felt okay rather than stand-out, and the resolution to Addie's business/relationship plotline could have been given more page time to be satisfying. Fans of easy-to-read murder mysteries or amateur detective stories will likely enjoy Kelly Mullen's debut.


(Thank you to NetGalley and the publisher for providing an ARC in exchange for an honest review!)

Thank you Penguin for the ARC of this book!

This was more along the lines of what I wanted with Mother Daughter Murder Night! This was a cute cozy mystery for fans of locked room mysteries, and who are able to put up with some incredibly cheesy dialogue.

The premise is pretty standard--everyone is gathered to a mansion under the premise of a nefarious auction, they're trapped in the house by the weather, and BAM! Host is murdered. Now we've got a team of a grandmother and her granddaughter working together to try to repair their relationship while cosplaying as Sherlock and Watson.

The overall story was fun and interesting, and I was definitely invested in the story, but the secondary plot points just weren't it for me. The video game designed bit had SUCH a strong potential, but it was really only every used to add in weird and random pop culture references and video game jargon and didn't really serve a purpose. And I really hoped her relationship/battle with her ex would play a bigger role than it did. It came and left in two sentence bits throughout the story, and I think it was such a missed opportunity.

Overall if you like a cozy mystery and don't mind some cheesy dialogue, this was a fast and fun read!.

This was good, but it was a little hard for me to follow. I couldn’t quite keep track of who was who/what they did. Honestly that could be more of a me thing. I also didn’t love the narrator’s voice so that might have been a contributing factor.

I definitely liked the premise of this book. But it just didn’t work for me.

Thanks to PRH Audjo for the early audiobook.

I enjoyed this. I thought that the characters were really well done, and the dialogue and banter was great, too. I thought that the mystery aspect was twisty and turny and I really liked that our MC was a mystery video game maker. I especially enjoyed that the mystery felt complex--I didn't feel like it was too surface level, or that the twists were easy to guess. Overall, I really liked this and I cannot wait for my branch to get our physical copies in!

⭐️ 5/5
Third Person POV, Dual Narrative
Linear Timeline
FMCs: Addie & Mimi
Setting: Mackinac Island, Michigan
Murder Mystery, Whodunit

Kelly Mullen brings us a clever, witty, suspenseful whodunit following the story of Addie, a mystery genre video game creator and her somewhat absent grandmother Rosemary, or Mimi, as they try to uncover the blackmail mystery Mimi finds herself in and the murder that shows up at an off-putting cocktail party.

This was a complex, tense, witty, and fun read! I enjoyed the twists and turns, as well as the banter amongst characters. I appreciated the relationship growth between Addie and Mimi as well, which added a perfect heartwarming and enduring element!

Thank you Penguin Group and Dutton for providing me this ARC via NetGalley for an honest review. All opinions are my own.

"The mansion looked like a vampire's lair designed by Henry VIII."
Septuagenarian Mimi is having a small blackmail problem and invites Addie, her (recently jilted videogame inventor) granddaughter up for a visit to picturesque Mackinac Island at the junction of Lake Michigan and Lake Huron. They need to go to a party at the mansion of the richest woman on the island despite the raging blizzard. That woman is a really nasty sort and is also the first one murdered and robbed of the jewels she wears. Let the sleuthing begin! Mimi and Addie work (kinda) together to investigate who else among of the many guests on this isolated island was being blackmailed and which one did the deed. Nearly all of the characters are more than a little quirky (except for the dachshunds) and the fun is as liberal as the alcohol.
I requested and received a temporary uncorrected e-book file from PENGUIN GROUP Dutton | Dutton via NetGalley.
#ThisIsNotAGame by @kellymullenauthor @penguinbooks @duttonbooks
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