Sublimation

by Isabel J. Kim

Sublimation is the debut novel by Isabel J. Kim, winner of two Nebula Awards, the Locus Award, the British Science Fiction Award, and the Shirley Jackson Award, and a finalist for the 2025 Hugo Award and 2023 Astounding Award.

The border cuts you in two.

When you immigrate, you leave a copy of yourself behind. One person enters their new country, the other stays trapped at home.

Some instances keep in touch, call each other daily, keep their lives and minds in sync in the hopes of reintegrating and resuming a life as one person. Others, like Soyoung Rose Kang, leave home at ten and never speak to their other selves again. Rose, in America, never imagined going back to Korea until her grandfather dies and her Korean instance calls her home for the funeral. When she arrives, she discovers that Soyoung plans to steal her body and live her life whether Rose wants to reintegrate or not.

Sublimation is a literary speculative fiction novel that pits the lives we choose against the lives we leave behind. It’s an immigrant story like no other, capturing the longing for another life and twisting it into a dangerous game of cat-and-mouse.

Genres: Science Fiction, Horror, Fantasy, Fiction, Adult, Speculative Fiction, Science Fiction Fantasy

368 pages, Hardcover

Expected publication June 2, 2026

About the author

Isabel J. Kim lives near New York City in an apartment filled with books and swords. She is the author of numerous short stories and has won the Nebula, Locus, BSFA and the Shirley Jackson Awards. Her work has been translated into multiple languages and reprinted in multiple best of the year anthologies. When she’s not writing, she’s practicing law or podcasting. Find her at isabel.kim, @isabel.kim on Bluesky, or @isabeljkim on instagram.

Reviews

[L (Nineteen Adze) · Rating 5 out of 5]

11/18/25: I just read the first POV segment last night, and waiting for the paper ARC in January/February so I can more fully engage with The Text (TM) is going to test my patience like nothing else. I (don't) apologize in advance for what a complete freak I'm going to be about this whole book. Second person writing? One great worldbuilding device with deep thematic implications? Emotions simmering just under the surface? She can't keep getting away with this.
--
The author's debut short story that this is based on absolutely slaps and you should read it immediately to acquaint yourself with this universe: "Homecoming is Just Another Word for the Sublimation of the Self"

I made a bunch of unhinged screaming noises when I saw the news that Isabel J. Kim had a book and media deal (Sci-Fi Novel ‘Sublimation’ Lands At Universal International Studios For TV Adaptation), but look, it's only because she's a genius and I have great taste.

The book is set in a world where a process called “instancing” splits a person into two distinct copies: one who migrates and one who remains. The story unfolds when a woman who migrated returns to Seoul and must face her other self, while her childhood friend’s New York self draws her into a conspiracy to control the future of instancing, bringing both versions of him back into her life with global repercussions.

Do we have a release date or any character names character details yet? Irrelevant. I can't wait to dive in.

[Ai Jiang]

A big thank you to the author and publisher for an eARC of the book for a blurb!!

SUBLIMATION is an odyssey of choices and regrets, of people who would be and never were but also are, all at once, exploring immigration and separation, diaspora and the resulting split identities of cultural interweaving—both willing and unwilling. Kim masterfully blends the experimental and straight forward, jarring yet familiar, philosophical and theoretical, while exanimating placelessness and fractured identity through multilayered narratives. I have never felt more seen by a book in my life.

[Mai H.]

ANHPI TBR

📱 Thank you to NetGalley and Tor Books

[Jay Brantner · Rating 5 out of 5]

This was an absolute joy to read.

If you haven’t read the short story it’s based on, I highly recommend checking it out. If you like it, it’ll get you excited for the novel. If not…well, it’s a good representation of the style https://clarkesworldmagazine.com/kim_...

This book does a wonderful job digging into the personal character moments. The second-person keeps the reader close while also providing something of a dislocation effect, as it stars characters who are constantly wondering whether their lives would’ve been better if they’d taken the other branch of big life decisions. It’s that internal turmoil that provides the biggest interpersonal conflicts and the true emotional heart of the story.

There’s also a thriller plot that builds over the course of the story and takes center stage in the fourth act. I’m personally biased against thriller plots, so your mileage may vary, but I don’t think it’s exceptional here—it struggles to motivate the kind of world-shaking stakes that the characters feel it has.

That said…the quality of the writing and the interpersonal conflict is good enough to make this a five-star read even if the thriller element isn’t top-tier. The climax hits the character notes hard enough that it never feels like they drop into the background, even as the story gets plottier.

It’s a very good book, and an even better debut. I wish I had done a better job of reviewing it. Perhaps I’ll clean this up and try again later. But right now, I’m adding my recommendation to the stack.

17/20

[thelamaesque]

I’m at NY ComicCon and they brought this book up at a TOR panel and holy hell I AM SO SAT. They pitched it as severance x immigration, so when you emigrate, you essentially sever yourself into two: the person you are in your birth country and person you become in your country of destination. !!! INCREDIBLE !!!

[Clara · Rating 5 out of 5]

holy sh*t this book is good

[Natalie Benkowski · Rating 4 out of 5]

4.5/5

this is one of the most unique book concepts i have ever had the pleasure of reading, so thank you to TOR and the author for allowing me to ARC read it.

this book dealt in the controversial and hot button issue of human migration, but made it digestible through a multi-tonal lens—this was a lecture and a retelling of myth as much as it was a linear storyline. this format choice as an approach to understanding such a dense topic really helped write home the themes of identity and exploration of the self in intersection with diaspora in a cross-genre capacity, which felt entirely nuanced. the world as an instanced version of itself takes a LOT of world building and science info dumping to understand, so unveiling that info in small bits chapter by chapter as is convenient for the storyline was a creative way to help the reader grasp the changes between our world and the book’s in a way that didn’t overwhelm. our main characters were raw and unfiltered, even verging on unlikable at times, as a strong commentary on the human condition, internal conflict, and the impact of choice. i have always appreciated books surrounding the dismantling of corporate overlords and corrupt government organizations by way of subterfuge and whistleblowing, and this book definitely hit the nail on the head there. there wasn’t much i didn’t love about this one outside of the slow start. it took me a while to really lock in and care about the characters as they were being presented and to feel like i knew and cared about them. it wasn’t until we got to know YJ better that i felt like the story really started for me, and i almost wish he/yujin would have been our introductory main characters instead of soyoung/rose as i found them a little one-toned.

i really loved this one and think it’s going to be massive once it releases in june. very high hopes for isabel j kim in her debut novel—this one definitely impressed!

[Josh Peterson · Rating 4 out of 5]

Wild ride. Absolutely dug this crazy story. The premise certainly had some SEVERANCE vibes but I absolutely loved how (a) it wasn’t really like that at all and (b) how fleshed out this world was. Great world-building and done in a way that never felt like information dumps for the sake of it. Super cool.

Fun story. I think people are gonna love this book.

Thanks to Net Galley for the ARC.

8.5/10

[Meire Albuquerque · Rating 5 out of 5]

WOW!!!!! Hooked from the first page and read this book in one sitting… Full of tension and suspense. A real page turner, a domestic noir but OMG so much more!!!!

[Clare · Rating 4 out of 5]

Thank you to NetGalley and Pan Macmillan for this ARC.
Sublimation, by Isabel J. Kim, is set in the present day, in a world we recognise, but with one major difference. In Kim’s created world, humans have always possessed the ability to ‘instance,’ to become two people, or more.
The novel initially focuses on Soyoung, who was born in Korea. As a child, she and her mother ‘instanced,’ and Soyoung’s instance, known as Rose, went to live in America. Since then, Rose and Soyoung have had no communication, living their lives in different cultures, and yet they share a childhood and all its memories. It is the death of their grandfather, Harbeoji which brings Rose back to Seoul. Harbeoji’s dying wish was that Soyoung and Rose ‘reintegrate,’ become one person again. This first section alternates between the voices of Soyoung and Rose, which are written in the 2nd person, giving a sense of intimacy, blurring of the boundaries between the two women. When the narrator refers themselves as ‘you,’ do they mean themselves, or their instance?
The story flows easily, arranged in short scenes, nuggets of encounters and thoughts, the writing elegant and nuanced. There are scattered paragraphs explaining how ‘instancing’ has always existed, how it ‘captures a static moment.’ … ‘The heart at the moment of stepping over a border.’ The writing evokes a sense of longing for a part of oneself that is lost. There is a sense of ‘sliding doors,’ what would have happened ‘if you had not gone, or had not stayed... A whole other life being lived by someone who is you.’
The theme feels very much of the moment – when we leave our homeland who do we become? What does it mean to be separated from yourself, literally and metaphorically. We learn that America, Rose’s adopted home, is populated by instances, who were made legal in 1776, at a time when it was assumed that they would stay and populate this continent. As the novel progresses, we gradually learn more about how instancing has evolved through history and culture. Kim does this with a lightness of touch, almost on a ‘need to know’ basis, inserting short paragraphs into the middle of scenes.
The story is woven through with references to folktales, handed down through the generations, as well as classical and Christian references. There is the story of a ‘returned’ fisherman, re-appearing to find his place has been taken by his other self. To destroy him might mean self-destruction. It is suggested that only by leaving can Odysseus return home a decade later and become himself, embracing his own faults. The story of Adam and Eve is referenced. These fragments of tales become more frequent as the story progresses, heightening certain moments with a significance, giving the reader an awareness of what is at stake for the characters. On one hand this can feel manipulative, even academic, but on the other, it allows us time to absorb the significance of what is happening, an awareness of the shifting layers. We are given various endings, how the stories might be interpreted, but ultimately these tales are inconclusive. Always we return the sense of something lost, a price paid for anything gained.
Later, we learn more about Soyoung’s childhood friend Yujin, and his instance YJ, again one in Korea the other in America. YJ works for Merge Break, one of the growing numbers of tech companies invested in the instance industry. YJ wants Yujin to have the option of YJ’s life, a green card, Dual Citizenship. They talk regularly, have a close bond. But we learn of chilling scenarios – the story of two instances – one a holocaust survivor, who is pushed off a roof by his instance, who cannot bear to live with the holocaust memories. YJ has two grandfathers, one in North Korea, the other in the South – who was ‘disappeared’ by the Korean government. There is a sense of the fragmented self, magnified by history.
Instancing has, so far, been an act of self will. This raises question of who owns the memories if an instance reintegrates? This is an echo of subjects that preoccupy us today, such as AI and intellectual property. The story touches on much that is significant in our world at a time of division and uncertainty – immigration, citizenship, borders, our sense of self, identity, belonging. How we delineate our world. Kim argues that the borders, artificial or not are “…a social technology, that creates emotional reality, that creates a physical reality.”
The pace and tension of the story speeds up when we learn about new technology which will open up possibilities for the control of instancing and reintegration, raising crucial questions about our right as individuals to exist in a place of our choosing. Our definitions of freedom.
Overall, the layering of characters into different ‘selves’ does mean that there are complicated concepts to grapple with and at times I found it difficult to fully empathise with characters that were split into different personalities. However, the elegant, lyrical writing, arranged in short vignettes makes the path generally easy to follow, even when it seems to meander and divert. However, as the implications of the developing technology around instancing forces events forward, the focus starts to feel fragmented. There are many questions, and there were times when it felt that these questions were too numerous to be corralled into any kind of answer. The understanding of what it is that essentially forms a person became scattered. I found it difficult to connect and empathise with characters who are in pieces.
On one level I appreciate the inconclusive style of this novel. ‘Instancing’ is portrayed as a physical reality of something that is psychological and relevant to us all. But in the world Kim has created, I questioned whether this physical manifestation would have had a greater impact on how we developed as a society. In Kim’s world, Humankind seems to have easily absorbed all the repercussions of this self-splitting. Surely it would have had a greater effect on how we view borders, societal divisions, and our awareness of our own self? This is not to say that Kim does not explore these questions, and it is this exploration, together with the beautiful writing, which makes this a fascinating and pleasurable read.

[Weronika · Rating 4 out of 5]

The novel poses a question that can haunt both immigrants and those who ever dreamed of emigrating but decided against it: What would your life have looked liked if you stayed? What would your life have looked liked if you went away?
Isabel J. Kim crafts a world in which people don't have to choose, their psychology chooses it for them. When they leave to a new country (& novel sets it up as any permanent travel regardless of national borders, i.e. sailors at sea or protagonists from fairytales), they may "instance": leave a copy of themselves behind; a life split in half. From then on, they share memories of their life "before" but are essentially two different (yet the same, like clones or doppelgängers) people, living two separate lives. What's worse, people do not know if they would instance: it seems, emotions regarding the departure dictate that and one of the protagonists did not expect that but still left his instance behind.

The novel has two pairs of protagonists/POVs, who had instanced between South Korea/USA and have contrasting approaches to it. Soyoung/Rose instanced as a child and never got kept touch with her other self. A funeral and last wish of their grandfather results in their first meeting in years. Yujin/YJ instanced unexpectedly to himself, when leaving for college. His both "selves" talk daily, play LoL together, and try to maximize their separate experience (education, visa and green card hopes - I like how immigration to the US and its complexities were a plot point here!) and micromanage their future (one is not seriously dating if another does) with the hope of "reintegrating" later. When two instances touch, they become "one" again.

This worldbuilding with all its logic, backstories (woven into the novel as historical instances of instancing or fairytales or social commentary) and emotions (who would people become when they reintegrate? does reintegration mean "death"? which life is more important?) is fascinating and I loved this premise! Unfortunately, it seems that the author put more energy and thought into that worldbuilding than into the actual plot and stakes. First of all, the novel is marketed as Soyoung planning to "steal" Rose's life, but the emotional urgency of this plot is lacking. I don't think Soyoung's motivations were explored well, especially that her life in South Korea does not seem to be worse than Rose's: actually, it seems better as Soyoung has a fiancee and a large family, while Rose only keeps in touch with her (instanced) mother and seems lonelier. The novel tries to push a belief that life in the USA is somehow better (YJ and Yujin also aspire to it) but... does not explain why? South Korea, as described in the novel, is a joyful place without any political oppression. This plot point would work much better in a fictional dystopia or in a time setting like Soviet Union/USA when emigration seemed to have different stakes than just economy.

Because I never understood Soyoung's motivations fully, I could not really connect with her as a protagonist. I like flawed protagonists, but she was sometimes cold and calculating, and a few pages later undecided and chaotic. I could not really root for her because I did. not understand her decisions. Her evolution from a character who cares about herself to someoone who cares about the world/others was also not believable. I found Yujin to be a more interesting character but it took a while to get to his POV.

There was a thriller/corporate thriller aspect to this novel that was not sufficiently explored and did not seem as menacing as it should have been. There was also a romance that was interesting and fun to read about, but ultimately seemed too rushed and its conclusion was abrupt and psychologicallly unbelievable. The novel seemed both too short and too long at the same time. Too short, because these thriller/romantic aspects seemed rushed and too short, because at times nothing was happening. I learned later that this debut is based on a short story and when I read it, the structure and dramatic tension was much better. Paragraphs about the worldbuilding were an essential/literary structure of the short story, while in the novel they got repetitive and tiring. I think that the author did not fully think through how to convert that story to a novel-length prose and simultaneously packed it with too much stuff but also did not develop the stakes/emotions fully. It was still an interesting read, but it was not as deep and engaging as the premise suggested.

I thank Netgalley and Tor Publishing Group for an Arc in exchange for an honest review.

3.5 stars rounded up (because it's a debut; but I'm sad about the lost potential).

[David Agranoff · Rating 5 out of 5]

Of the most anticipated science fiction novels of the year, this debut is on many radars. This novel didn’t have the standard struggles of a debut. Isabell J. Kim, for one, has won the Nebula, Locus, BSFA, and the Shirley Jackson Awards, and she has a well-earned reputation for really good short fiction, including several you can read for free over at Clarkesworld, including the story that was expanded into this novel. The novel went to Tor in a bidding war and has already sold TV rights to Universal. All amazing things, but there is only one downside.

Major hype puts more pressure on the novel. As I write this review, the official release is months away. I was a little worried that the novel would not live up to the buzz.
The good news is that, yes, the novel is fantastic. Another thing about the buzz, because of the timing and the marketing, which is constantly comparing this show to Severance, it might be easy to dismiss this novel as chasing Severance vibes. Let's keep in mind that Kim first explored this idea in this short story…

https://clarkesworldmagazine.com/kim_...

More than a year before Severance, you can’t blame Tor for going there, as the Apple TV show is great watercooler SF. That being said, Sublimation and Severance share some conceptual DNA, the tones are very different. Sublimation is not a mystery box; the concept makes it an alternate history in a way. I wish I didn’t have to compare them, but that is the fate of this novel when it is marketed as such.
The more natural comparison for me was last year’s top read, Luminous by Silvia Park, an SF novel by a Korean American author, whose work was shaped by both cultures. Luminous, of course, is a robot novel, but both novels are about immigration, although this one is much more direct.

Sublimation is high concept SF that skirts with Twilight Zone-ish off beat just barely fantasy vibe. I say this because the process of an “Instance” process is almost magically fantastic, but treated in the novel as just the natural way of the world. In the universe of this novel, immigrants who cross borders split into versions of themselves. One that stays home, and one that changes and grows, are separated in a new country. Much like PKD’s Counterclock World, it is more of a surrealist concept than SF, but Kim commits to world-building.

Soyoung Rose Kang became an instance when she traveled across the border. It is an interesting element of the theme that borders become essentially magical portals. Much like PKD’s Counterclock World, it doesn’t help to overthink it. This idea is excellent for exploring themes and not one for readers who nitpick or ask lots of questions.

Rose and her mother left Korea as children. When they crossed the border, they split into two copies, and the old Soyoung stayed behind, living a separate life. Did she become Rose in America, or was Soyoung created to stay in Korea? As Dickian, I love the questions about what is real, who is human, and who is not. Who is living a REAL life?

The story kicks off when Rose is asked to travel back to Korea for her Grandfather’s funeral. She hasn’t been back since she was ten. Rose has become American, but at ten, a version of herself continued to grow up in Korea. Her relationship with her Korean mother is very interesting; it looks and sounds like her mom, but of course, she is different. Rose has some memories of Korea, but America is a mystery to Soyoung. You might be able to guess where this is going.

One way to tell this story might have been to have a person at an agency overseeing multiple cases, but smartly, Kim tells a focused story based mostly on two experiences. It is enough to really highlight how immigration is a part of our fabric. “Instancing is written into America’s blood, into the story it tells itself. Here is where instances immigrate. Give us your tired, your poor, your hungry, give us your copies and let them be fruitful and multiply, let them homestead, let them become titans of industry, let them and their non-instanced children build cities, towns, and railroads.”
The surreal existence of the instance gives the novel a chance to explore with and play with themes that are part of the American experience, high concepting the issues doesn’t exactly bury the issue either. This novel has a point of view.

Much of the narrative tension comes from Soyoung/ Rose dealing with the weird ways their lives are forced into drama by the splitting of their lives. They were one person, now they are two, the same childhood and family but after ten years old two very different people. “It’s not clean,” she says. “I want the sort of clean, perfect separation like we pretend that these last months never happened, with all my memories sectioned off into the right person who needs them.”

It is on the back cover, so it is not a spoiler, but Soyong tries to steal Rose’s life. The parallel stories are much of the story's driving force. The POV shifts often, but it slips gently into second person in certain chapters.

We also get the story of an ambitious instance named Yujin, whose two separate halves work together with separate educations, with the intention of becoming one person later. Yujin’s story is the perfect parallel because Rose and her Instance want nothing to do with each other. Yujin explains his desire to be one, while Rose sees integration as theft.

“So, it’s like – I want to remember being home. Living at home. And Yujin wants to remember ten years of being here. And Yujin wants to skip military service, if he can. And I can’t go back without potentially getting flagged for my own military service. Or becoming him and having to do his- ours?- and this way we get everything. All of it.”

Soyoung nods. “Yujin wants your life. He wants your life, he wants your life. Soyoung wanted Rose’s life.”
Yujin, however, was strategic.

“You had gotten the science degree, and Yj had gotten the business one. You agreed to this to maximize your abilities later, after you reintegrated.”

The novel explores plenty of corners presented by the concept. Enough to feed a TV show, but also enough to give the novel plenty of dynamic corners.

“Imagine a world without instances. A world where leaving is a perfect absence, where there is no ghost left behind. Imagine knowing the parallel, leaving the past in the past, a world where desire doesn’t matter, where there is knowledge of the implicit truth of the human heart.”

This is wonderfully opinionated science fiction. The Severance comparison negatively affect readers who are looking for a workplace satire, and since I am the PKD guy, I think Philip K. Dick fans will enjoy the concept. The prose is excellent, and Kim plays with tense and form in many interesting ways. The characters are well drawn and will pull you into the end world enough that you will just go with the more surreal elements. This is a great modern SF novel that deserves attention.

[Andrew · Rating 4 out of 5]

I don’t normally read much science fiction, but I was attracted to Sublimation by Isabel J. Kim because of its use of doppelgangers and its central theme of migration. I’m glad I took a chance on it.

The world of Sublimation is mostly like our world, but with one key difference: the phenomenon of “instancing”. When people leave one country to go to another, they often leave behind another version of themselves. They are doubled, in other words, with one person living in the new country and an identical person staying behind at home.

“An instancing captures a static moment. A feeling in a specific time and place. The heart at the moment of stepping over a border. The mind when it knows it is leaving.”

Of course, they may be identical at the moment of the instancing, but the two versions of the same person then have very different experiences and become different people over time, which is where a lot of the plot development comes from.

What I found fascinating about instancing is how it’s a sci-fi device that sheds very interesting light on the reality of migration. When people leave their home and move to another country, they often talk about leaving a piece of themselves behind. You could easily read Sublimation as a kind of extended metaphor to capture that feeling of duality, the fracturing that can result from being ripped out of one reality and starting a new life in a foreign land.

Soyoung left Korea with her mother at the age of ten and moved to America, where she became Rose. The American instance, Rose, has never met or even spoken with her Korean instance, Soyoung—the one who stayed behind. The death of her/their grandfather prompts her to go back to Korea for the first time, where she encounters not just her own instance but also the Korean instance of her mother.

I won’t spoil the entire plot for you, but I will introduce one more concept: reintegration. It’s possible for the splitting to be reversed, for the two people to become one again when they meet in person and share physical contact. It’s possible for that to happen even if one of them wants it and the other doesn’t.

The result is a new person with the experiences and memories and desires of each individual, but no separate individual consciousness any more—they’re a single person, with all those conflicts tainting every memory, every relationship. They’re a different person, and friends and loved ones of the individual instances are now part-intimate, part-stranger.

“Every bit of the past feels fake from the dissonance, the sheer divorce of her past selves from her present decisions coloring even the combined memories. Her prior emotions are dead things in her chest. Like the stickers she saved as a kid, pretty little scraps of paper that meant something a long time ago, but have no meaning now.”

Plenty more happens after that, and after a fairly slow, thoughtful start, the novel picks up to a thriller-like pace towards the end. It’s all quite enjoyable and is resolved in a satisfying ending, but what I liked most about Sublimation was its exploration of the concept of identity.

We tend to think of ourselves as solid, stable entities, but of course we change all the time based on the decisions we make. If I’d never left England, I would be a very different person from the one who left at 22 and has been bouncing around the world ever since. If I met that Andrew who’d stayed behind, how much of him would be recognisable? And if we reintegrated and I suddenly had to deal with his/our wife, his/our children, his/our life, how would I cope?

On the other hand, how much of that other Andrew would be the same as this one? That sameness that exists beyond the divergent memories and relationships is probably my core identity. But it’s interesting to think about how much of who we are is changeable and shifting, dependent not just on big events like migration but on every decision we make from day to day, the large and small ways in which we step into new realities and leave others behind.

Thanks to NetGalley for an advance review copy of Sublimation, which will be published by Tor Books in June 2026.

[Maya · Rating 4 out of 5]

Thank you to NetGalley and Pan Macmillan Picador for providing me with the ARC.
Pub Date 9 Jul 2026
A sci-fi literary fiction with strong social commentary. I was fascinated with the concept of “instancing” presented here. In this speculative reality the physical crossing of a border splits a person in half, or more like creates another version of that person, who is also the same person, but going into the world and having different experiences. If you ever wandered what would’ve been like if you went to study abroad, or decided to go live in another continent, this plays with that idea of having two lives.
At the beginning we are following Rose/Soyoung, but I was pleased to see that we get the POV of YJ/Yujin as well. Rose and Soyoung are the same person, but to me they read as very distinct. I applaud the author for being able to write one and the same character and still managed to get me to feel differently about each of them. The same goes for YJ and Yujin.
The narration switches between second person and third person narration. I felt like this was very imperative to the feeling it wants to create, simultaneously putting you in the character’s place and then splitting you from it. There are scientific aspects that are included and it was really interesting reading the paragraphs that add more of a clarification to the reality of “instancing”. Everything is based on intent and choices and it’s deeply psychological. The desire for more and better.
But there is also a dissonance, that makes a person doubt and regret, which is a big drive for the plot here. In the last two halves of the story we get into the bigger picture and it was very exciting. Not to spoil anything, but the plot thickens and it made me breathless. But I had some conflicting feelings about the main character Soyoung – I can absolutely relate to her, but my God, she was an awful person in my opinion. The way she treated her other self and her friend and her fiancé, I was really angry with her. Her views were also childish, like when Yujin said to her that you have to live with your choices, she just responded – no, you don’t. Which was girlllll, you DO! Her arc was good, although I still think she was mostly selfish.
I think this book will resonate with a lot of sci-fi readers, it was expertly written and it was so rich with commentary and ideas and a personal dissection of one’s self.

[Elisabeth · Rating 4 out of 5]

Just a note, the following review will just be me raving about how incredible Sublimation was: Kim’s capacity of sci fi imagination being able to thread philosophical and ethical points is beyond impressive; Sublimation was truly poetic.
Imagine a world just like this one, but when you migrated to a new country, your body would instantiate into two people: one who stays in the homeland and one who immigrates and moves on. The two beings continue their lives this way, unless they choose to reintegrate back into one person. This story foundation is one that millions of first and second gen immigrants can resonate with— the what ifs of immigration, the idea of your “truest” self, always being torn between two world. In Sublimation, it’s been twenty years since American Soyoung (called Rose) has returned to Seoul. Korean Soyoung had called her with news of their grandfather’s death, and Rose is part of the will. We follow both their POVs, each in the second-person perspective, as they meet for the first time with conflicting feelings of familiarity and jealousy. I don’t want to give away too many plot points, but events start spiraling out of control, giving way to learning about the circumstances of others’ instances, traveling to different countries, unintentional reintegration, and ominous new technology.
Kim smartly writes this novel in a sci fi thriller manner, but intersperses the action with reflections on mythology and religion, and how they pertain to instancing and human nature. No detail is left behind in this story: instantiation is not at all theoretical but is very real, from Kim’s rewriting of world history to the modern day questions of visas and finances. We are forced to contemplate what makes up a person, how much is determined by memories and our environment. How much does yearning and desire encompass a need to stay or migrate, and what does it take to make the difficult but bold decisions in our lives?
Every section and chapter is FASCINATING. Kim’s writing of her characters and their choices is so layered and complex; the differences between instances and how they interact and understand each other is so meta and incredible to watch unfold. It’s a dark but brilliant story that feels realistic and relevant in our current age. Thank you Isabel J. Kim and NetGalley for this ARC!

[OddPittPatt · Rating 4 out of 5]

This one was a tough read and a little twisty turny but overall I really enjoyed it

the concept of a world where you split in two at the point of crossing a border was fascinating to me when I applied for a copy. The story kept that fascination and built a unique alternate reality where this is the case

while I was always at the point of having a million questions this did well to answer as much as it could about the logistics of instanceing and how the world manages it. There is mention of some specifics (like korean military service) and items like citizenship that help flesh out the world and help it make sense. There was a lot of information to keep up with though so I struggled to read it in bug chunks as you are having constant information thrown at you.

something I did enjoy was the little stories based on myths and legends scattered through out. each one linked to each perspective you see and it helped add context to how the character really felt in that moment without spending pages and pages going through it. it was a nice touch

the story overall was good but did feel a little bittersweet at the end. I won't spoil but there is an element of it that always leaves me feeling that it nullifies the whole struggle of a story but it was done it quite a nice way so I can't say it too much away for me


it was a fun read and may be one I will re-read to try and get a firmer grasp on it all! I do like the whole question of who do we become if we lived different lives and how much of us is inherently us and how much is a product of our experiences. Then what would you do if you actually could have lived more than one life would you choose to combine them into one? It is one that gives you alot to think about after!

[Jess Reads Horror · Rating 4 out of 5]

Thank you NetGalley and Tor Publishing for this ARC.

What happens when you live in a world where you can instance, or create a duplicate of yourself, lead completely separate lives, form separate memories while sharing memories you’ve had before instancing? Soyoung/Rose and Yujin/YJ, two childhood friends find out what it means to instance, find yourself, and decide the next steps in their life.

There is no way to give a quick recap of this book in just a few short sentences. My recap is honestly kind of lame, so please keep reading if you’re still deciding. First off, this was an incredibly complex and original premise, and i am so impressed with how a debut novel was able to pull this off. Complicated and foreign concept? Absolutely, but the author does an excellent job explaining it bit by bit, using Arirang, Odysseus, and Genesis to support this idea. Genius.

Soyoung and Yujin, the protagonists, are flawed and while not exactly likable, they are relatable to a certain degree, and just… human. They makes choices based on their circumstances, they say things that reflect their feelings, selfish or not. The supporting cast also made a pretty strong impression with me (Minsoo, Tae, Megan, Drew), because everyone makes an impact to the main character’s decisions and feelings, big or small. The multiple POVs was very easy to navigate as well.

This isn’t just a story about identity and self. It touches on broader subjects like immigration, cultural identity, and all the blessings/curses that come along with it. Very timely, and very relevant. Of course, everyone has a different story, but I believe immigrants can all find a piece here or there that may be relatable.

[Brittney · Rating 5 out of 5]

🫧 SUBLIMATION by Isabel J. Kim
Out June 2, 2026 | @TOR

Literary Speculative Fiction • Diaspora • Dual Identity

“When you immigrate, you leave a copy of yourself behind.”

What a concept. What a book. What a world. 🌏
Isabel J. Kim’s Sublimation is an existential fever dream. It's a story of immigration, identity, and the dangerous longing to reclaim what we’ve left behind.

When Rose crosses the border from Korea to America, another version of her, Soyoung, stays behind. Years later, a funeral forces their worlds to collide, and what begins as grief unravels into a haunting game of mirrors and survival.

This debut is speculative fiction at its sharpest with equal parts psychological thriller, diaspora myth, and meditation on belonging. Kim writes with the precision of a scalpel and the ache of a poet. Every sentence hums with questions of who we are when the border splits us in two.

✨ Themes:
🌗 Immigration & identity
🩸 Split selves / doppelgänger tension
💔 Cultural dissonance & memory
🧬 Philosophical sci-fi + literary prose
🌌 Korean diaspora / speculative reflection

For readers who love Ling Ma, Carmen Maria Machado, and Kazuo Ishiguro, Sublimation will absolutely destroy you ... beautifully.

#Sublimation #IsabelJKim #LiterarySpeculativeFiction #DiasporaStories #ImmigrantNarrative #SpeculativeFiction #BookishCommunity #FictionRecs #Bookstagram #AsianAuthors #SciFiMeetsLiterary #UpcomingRelease #BookishLove #LocusAwardWinner #NebulaWinner #MustRead2026 #DualIdentity #TORPublishing

[Cori Samuel · Rating 5 out of 5]

Phenomenal speculative fiction exploring what it might be like if we as immigrants could both leave and stay.

I came to this via the short story, Homecoming is Just Another Word for the Sublimation of the Self (link goes to Clarkesworld, there is also a human-read audio version there.) The story is developed for the book, but the style is the same -- in particular, use of second-person to convey the intimate weirdness of 'instancing', described as:

Instancing is not a physical phenomenon. It is not a cleft of meat and bone, there is no physical severance. It is the cleave of one future from another. It is psychological change as denoted through physical reality; it is metaphor made flesh. The physical effects are downstream from the higher-order changes taking place.

I loved how the similarities and differences of the main characters, two pairs of instanced people, are explored -- how leaving or staying is changing them. I also love the interweaving of cultural and societal reflections. Often, spec fic focuses around the impacts of the premise on the characters, but here the author has an exceptional range of vignettes across science, literature, history, myth and religion too.

Highly recommend you check out the short story, and if it piques your interest, pop this on your TBR for June/July. I'll definitely be rereading for all the nuance I missed first time through.

Rating: 17/20.
This review is based upon a complimentary advance reading copy provided by the publisher.

[Megan Manzano · Rating 5 out of 5]

Thanks to the publisher for an ARC!

This book has an incredibly unique premise: an instance of yourself can be created as you cross a border. What does it mean to have two selves leading two different lives? These are only some of the big questions that are grappled with in the book. Others include the immigrant experience and how that impacts your identity, your place of belonging as well as tension between Japan and Korea that has existed for many years.

I found myself amazed by this book for the plot and that it is almost entirely written in second person. This is no easy feat and Kim makes the experience so smooth I'd forget sometimes. You feel so often you are the characters and as stakes heighten and instances blur, you are on a fast-paced journey the entire time. You have no idea if the characters will instance or reintegrate, if a corporate institution can be taken down, if a romance will work out, if there will be a home to go back to but I'll say this, you will be curious.

[CC Rob · Rating 3 out of 5]

This is a great interesting take on thriller/sci-fi genre mashup. When you move to a new country, you leave a copy of yourself. Meaning one of you goes and the other stays behind. Main character Soyoung Rose Kang is one of the people who does not stay in touch with her copy after leaving home. But, her copy now has the opportunity and motive to steal her body back after their grandfather dies and the original is called home for the funeral.

This gives me vibes of all the great 2000s movies about cloning and the consequences. The writing is great, however I do want to mention, for me atleast, it was very hard to get into and took a while to finish due to the 2nd person style writing. If you are accustomed to that, it will be easier for you though. I really wanted to finish this since I was highly interested in the story and reviewed as advanced copy, but I really had to push myself, unfortunately (2nd person is not for me).

Overall, premise was great and would recommend it to anyone interested in this kind of sci-fi cloning thriller.

[Jennifer · Rating 4 out of 5]

3.5 stars rounded up.

It took me quite a while to really adjust to the writing style and get invested in the story, but once I got there, I started to enjoy this book. Each chapter is not only from a different character's point of view, but there are also several asides in each that are short of mini-throughlines in the book. It is, obviously, about immigration couched in a sci-fi, high-tech world. I appreciated that the various characters were coming at instancing/immigration from different places - I think it will both help a wide range of people find something to connect to in the story as well as expand one's understanding of this issue. It certainly made me stop and think about the various viewpoints surrounding immigration in the US.

Overall, I enjoyed this book and would definitely try another from the author. Thanks to Tor Publishing for sponsoring the Goodreads giveaway that let me read an advance copy of this book.

[Y · Rating 2 out of 5]

2.5⭐ I was really intrigued by the concept of the story, the splitting into multiple versions of yourself, I thought it was a neat idea with interesting storytelling potential, like the parallel universe idea but staying in the same world together.

That said, it unfortunately developed a bit too slow for me overall and I found the writing often repetitive - to me, some strict editing condensing everything significantly would have improved the reading experience a lot. On the other hand, the main characters' actions sometimes seemed very sudden and not supported by prior thoughts shared with the reader. The side characters were minimally developed, the main focus is really on two main characters.

The idea of merging back into one person reminded me (for obvious reasons) strongly of The Merge by Grace Walker, and I felt similarly about the pacing of that book, so if you were into that, I think Sublimation could work well for you and you should give it a try!

[Isabel Kim · Rating 5 out of 5]

i had to read this book a million times during the publishing process and i still think i did a pretty good job at putting words in front of each other in some sort of meaningful order. someday i will write a better book than this (hubris, to assume that my books will get better), but this is the best book i could write at the time (fact).

the coolest thing about this book, so far, is that when people read it and talk to me about it, they always tell me something interesting about their past or their family's past. and its really shown me how...everyone is from somewhere. we all have roads that we could have taken. lives that we could have lived. places we could have been from. my god. all those untrod roads.

but anyway, i hope that if you read sublimation, you also feel weird about the trajectory of your life and have a weird conversation about it. what else is a book for. ok bye. thanks for reading.

[Mary Robinette Kowal · Rating 5 out of 5]

Sublimation is one of the most powerful debut novels I've ever had the pleasure to read. It began blowing my mind from the first page as it explores self and the way memory and experience shapes us. It's about diaspora and regret and longing.

In this version of our world, when you cross a border you have a chance of instatiating -- ie becoming two versions of yourself. One who goes and one who stays. Becoming an Instance is like quantum mechanics in human form. Throughout the book, we get glimpses of the way instances have been woven into the history of the world with excerpts of folk tales, the Odyssey and Genesis. And all of that is before we get to the deeply human POV characters.

I started recommending this book before I was finished with it and then Isabel stuck the landing. Holy cow. It's so good.

[Hill · Rating 4 out of 5]

Wow, this was really cool. I would suggest reading as little as possible about the book before you read it. Just enough to know you're interested. Recommended for sci-fi fans that like a good story, complex existential questions, and interesting characters. Especially characters that are realistic and aren't always necessarily likable. If you need the author to describe in such vivid detail how the science in the science fiction works that you feel like you could build it yourself in your basement if you could only get your hand on some rare metals and schematics, you won't find that here. This has a more philosophical bent that will give lots to ponder. Going with 4 stars for now, but if it turns out to be one of those that I keep thinking about for a while I may change to 5.

Received advanced copy in Goodreads giveaway but this has not influenced my rating or review.

[Nicci Obert · Rating 4 out of 5]

I love speculative fiction that commits to a wrinkle in the fabric of reality and weaves it into the social and technological realms. World building was excellent. Characters were relatable, and the treatment of the differences wrought on the instances by travel, experience, and memory was fascinating. I didn't love the chapter-enders that retold different mythologies... they felt tacked on sometimes, and inconsistent, but I liked the idea of them. Overall, really well-executed story that made me thing; I anticipate I'll be ruminating on this one for a while.

[Sabina · Rating 5 out of 5]

(4.5) LOVED this. As someone fascinated by the daily tragedy of leaving things and places, the concept of the self being divided by departure grabbed me immediately, and the rest of the novel did not disappoint. I’m obsessed with how original and unique this felt!!! A debut that I highly, highly recommend for anyone looking for great scifi stories and conversations on interiority and immigration. Also could this potentially be the year of the doppelgänger???? Send all doppelgänger stories my way please and thank you!

[Audrey · Rating 3 out of 5]

This was a great concept and really well executed. It took a hot minute to get used to the second person. And the second person narration was so necessary to convey the perspective. When a person migrates, their selves are figuratively torn in half, part in the new country and part in the old. In Sublimation, it becomes literal and how each person handles their "instance" becomes a personal choice in how one approaches the past, present and future. A truly thought provoking read.

I received an arc from the publisher but all opinions are my own.

[Troll McGee · Rating 5 out of 5]

I was holding my BREATH during so many parts of this book. Bizarre and heartrending and poignant—I’ve never read anything like it! Worked for me as more of a vibes-based scifi/magical realism than as strict science fiction, but I think that was the point. A book whose questions produce more questions and leave you with a lot to think about. At times a quiet emotional drama and at others a crazypants thriller. I also really loved all the interjected myths/stories. Odysseus and the Auraji…

But ultimately fav thing was these characterssss. So human and selfish and lovely. Yujin and Soyoung <3