Thank you NetGalley and publisher for this arc!

This was such a good book. I really enjoyed it. More than I thought I would. I loved the writing style. This book had me hooked from page one. This is a first for me by this author but will not be my last!!

This is a story of family, of loss, of Riccardo, a young struggling writer, who is on the brink of being evicted, so when a stranger arrives at his door with the news that his grandmother has passed away, leaving him to inherit her villa in Milan, including her collection of butterflies, he leaves with little hesitation. This is just what he needs.

When he arrives in Milan, he is somewhat surprised by the changes in her villa, although many years have passed since he was there, he remembers how lavish it was when he was much younger. Even the butterflies held in their glass cases seem to have lost their beauty, and her villa seems to have deteriorated over time.

While there are moments of despair, and moments of danger, as well, this is listed in the horror category, so I appreciated the lack of what most consider horror since I’m not a fan of that genre. There are some lovely moments, as well. To me, it felt like magical realism with a sprinkling of some moments of danger.


Pub Date: 08 Apr 2025

Many thanks for the ARC provided by Harlequin Trade Publishing / MIRA/HTP Books

This book was read as an e-ARC received via NetGalley. All opinions are my own.

Rated 3.5 stars

Their Monstrous Hearts is a gothic mystery with horror elements. Riccardo is a struggling author living in Paris, who comes back to his grandmother's estate in Italy to attend her funeral. He notices strange things about the way his grandmother's friends are behaving, and notices changes in the estate. He finds a book with his name on it, and proceeds to read a detailed memoir of his grandmother's life. As the story progresses, we learn more about the mysterious butterflies and their significance to his grandmother (Perihan) and to the overall story. The gothic, horror-style elements build slowly, but definitely ramp up more towards the end of the book.

The story is interesting, and if you like a slowly-revealed mystery/secret, this could be a great book to read! Perihan starts her memoir by reminiscing on her childhood in Turkey, and her character arc as we learn more about what her childhood was like, and what matters to her.

Thank you to Netgalley, the author, and the publisher for the opportunity to read this enticing story!

Their Monstrous Hearts by Yigit Turhan was a wild ride from start to finish.

We meet Perihan and are quickly met with a scene that can only be described as ominous. From there, we meet Ricardo, the grandson of Ricardo, who is an author struggling with writers block, but also struggling with his current living situation.

An old friend of his grandmother's comes to find him and convinces him to leave Paris and to return to Milan as a family tragedy happened and his presence is required.

This story had an aura of mystery and eery secrets! I enjoyed reading Perhian's manuscript and thoroughly enjoyed the way the author created a beautiful and terrifying blend of two lives being told together. One from the perspective of Ricardo, and the other from Perihan.

This book was NOT at all what I expected, but it was better. It was a definite 5 star read. The last 30 percent of the book left my grappling for answers.

Pick this book up when it becomes available if you enjoy horror, mystery, family secrets, and horrible creatures!

Was different than I expected but was definitely a good time I can’t wait to purchase an actual copy for my shelf

Have you ever read a book that was filled with mysteries & horror? Well, this book is filled with dark mystery that will have you on edge. Just imagine having the power to turn humans into monsters with butterflies helping the transformation. This is definitely a good book.

This book was good at keeping my interest but some of the plot was difficult to understand how it flowed, i found myself having to go back and reread a lot. I also didn’t understand why it was considered horror until the action happened in the last 30 pages. The build up took a while but i did appreciate the storytelling in the manuscript, I liked how it was presented as a dual timeline basically. Thank you to NetGalley and Harlequin Trade Publishing for this eARC

I liked this book more than I thought I would! While I normally don’t pick up horror-type books, I really enjoyed this one! I think it’d suit anyone who really loves creepy books with clues scattered throughout the chapters! I’d love to reread this after it’s published during the fall months (probably around Halloween lol).

Many thanks to NetGalley for the arc!

I mean, Their Monstrous Hearts by Yigit Turhan wasn’t bad, but it was definitely one of those books that felt like it was trying really hard to be deep and eerie, and it just… wasn’t hitting for me. The vibes were all there—gothic villa, creepy butterflies, mysterious old ladies—but somehow it all fell flat. Riccardo’s whole “struggling writer finds himself in a haunted estate” thing felt more tired than tense, and honestly, the butterflies were more interesting than half the characters. I didn’t hate it, but it didn’t give me the chills I was hoping for. Maybe it’s your vibe if you’re into moody atmospheres that don’t quite deliver.

Thank NetGalley, Harlequin Trade Publishing, and the author for an ARC of this book!

Their Monstrous Hearts follows Riccardo, a failing author, who has just been informed of his grandmothers passing. Being the sole heir to her estate, and having no other options, he finds himself traveling to her funeral. Riccardo feels something is not quite what it seems and on his self guided tour of the house he finds his grandmothers diary. Hoping this may help him find out how her mysterious death came to be, as well as give him inspiration for his own manuscript, Riccardo begins to read only to find a more mysterious side of his grandma than intended. The further he makes it into her diary the more his life is at risk. Will he find what happens to Perihan, and if so will he make it out alive?

Overall I enjoyed Their Monstrous Hearts. I lked this horror genre, but found the middle was a little hard to read which is why it took me so long to finish this book. I enjoyed the beginning, and the ending but something about the middle was lack luster and nearly had me not wanting to finish the book. However I really wanted to know where the butterflies came from and the significance and hold they had on Perihan.

3.5 stars rounded up to 4 stars.

This was a propulsive gothic horror that I think would translate SO well on the big screen! THE BUTTERFLIES!! The horror! The fashion! The locales! I could see A24 picking this novel up for adaptation.

My favorite part of this was Perihan’s manuscript! It was WILD. Fantastical. Unbelievable. Fascinating. Creepy. Also, if you are a fan of a book within a book, this will hit the spot.

I read this in 2 days and I don’t do that often. My pace is usually 1 book in 7 days

One of the only critiques I have is that the writing style wasn’t my favorite. It was a bit repetitive, using the same descriptive words repeatedly (‘uneasy’ being one of them). But I NEEDED to know what was going on so I plowed through this. If you are a fan of horror films like Get Out, Hereditary, or anything by David Lynch, I think you’d enjoy this!

I found this novel to be very intriguing and atmospheric! I think Turhan's writing really shines in Perihan's manuscript entries, as it provided a deep look into the character's mind as she falls deeper within the trap of power, obsession, and madness. The pacing was a little off in sections, especially since it was slower in the middle with a quick escalation to the ending, and sometimes I felt as if the descriptions and character interactions didn't leave room for the reader to infer feelings and motivations behind the characters. But as someone who loves a moody horror story with a good bit of symbolism, I'd definitely recommend it!!

I really enjoyed this one! A perfect blend between horror and intrigue. I truly was impressed as this was my first time reading this author. Thank you to NetGalley and the publisher for allowing me to read this in exchange for my honest opinion. There were moments when I was unsure what was going on and had to reread but otherwise a great novel.

Their monstrous hearts is both a haunting and atmospheric novel that will captivate readers that crave a dark suspenseful tales of obsession and the blurred lines between reality and madness. For fans of psychological thrills and literary fiction that are looking to explore madness and the lengths people will go to purse their creative passions.

If you're looking for a gorgeous sprayed edge, stenciled hardcover, this is for you. It's gothic and frankly terrifying. I love found-manuscript and found-diary stories and this satisfied that craving in full!

Thank you to NetGalley for the copy of this eARC in exchange for my honest review.

I want to thank NetGalley, Harlequin Trade Publishing, and the author for this ARC

5 Stars ⭐️⭐️⭐️⭐️⭐️

Initially the cover and title alone were enough to peak my interest. I was pleasantly surprised while reading at how beautiful this gothic horror tale truly was. The authors talent left me in awe at multiple points throughout the story.

This story centers around the main character Riccardo, an author struggling to complete his manuscript, running thin on both funds and motivation. Everything changes when he hears news of his grandmother’s passing. Although he had not seen his family in many years, she left him both her estate and fascinating butterfly collection. After discovering her manuscript, a darker mystery reveals itself.

Each character introduced was so beautifully fresh and unique I couldn’t help but find myself drawn in farther.
I devoured this book in a single day, which I do not do often!

I would highly recommend this story to anyone looking for a great Gothic tale, beautifully written horror, and an on the edge of your seat thriller.

A dark frame story within a story tells of young Ricardo returning to his grandmother’s Billa in Milan after receiving news of her death. Here he finds a handwritten manuscript of her memoirs that tell a bizarre and fantastical tale of her life and the dark magic within it.

This was a macabre story of transformation, immortality and the corruption that comes with power. At some times disjointed or conflicting (Ricardo’s mother’s story was a non-story with no proper fleshing out or explication and some dangling loose ends) it is written in a lyrical voice that does compel you to keep reading

This is an excellent horror novel! I will recommend this to any who enjoy both horror novels and novels that hold deep symbolism within them. There are some pacing issues in the middle of the book, but the story and characters make up for it. This novel did excellently with keeping a creepy tone and unsettling atmosphere throughout the novel. It is like the setting has become a main character that you can feel throughout the book. While reading I also got a sense of being in the same vein as Mexican Gothic by Silvia Moreno-Garcia, which is another favorite story of mine. I was surprised that the main character isn't really Riccardo, but it was fun to experience that shift.

I started stepping out of my comfort zone and trying new genres, and the title and cover of this book had me instantly interested! I absolutely loved how unique this book was. The plot and character development was so intriguing I couldn’t put my kindle down!!! Definitely a good read!

This is a bit of a mixed review. Most importantly, I enjoyed the book and found it thrilling and compelling. The pace was exciting and the narrative structure, intertwining two narratives past and present, led to the fantastic climax. The downside was the relationship building, the character building felt rushed and the feelings the characters had for each other felt inauthentic. Overall the imagination and creativity and excitement were enough for me to look past this and truly enjoy the novel.