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Cold Heart
The perilous, isolated continent of Antarctica. Newtopia City, two kilometers beneath the ice. And something, stealthily, growing.
It’s 2063, decades after magic returned to our world. Leeth, raised at the Institute for Paranormal Dysfunction, is now a government assassin. But sent to Antarctica, to the city run by the world’s first truly sentient AI, her new mission may be impossible. In the city it controls, under its all-seeing eyes, she must somehow find and destroy both the AI itself, and the technology it stole.
But how do you kill an AI that has successfully hidden and protected itself for years, while secretly running a global megacorporation?
Why did the AI steal technology for rewriting human memories? Why is it holding four young gifted orphans in a hidden research facility? And why has it begun inexplicably crashing?
But when powerful entities reach out from the shadows, and a primeval land awakens to magic, things are guaranteed to get strange – deadly strange.
It’s 2063, decades after magic returned to our world. Leeth, raised at the Institute for Paranormal Dysfunction, is now a government assassin. But sent to Antarctica, to the city run by the world’s first truly sentient AI, her new mission may be impossible. In the city it controls, under its all-seeing eyes, she must somehow find and destroy both the AI itself, and the technology it stole.
But how do you kill an AI that has successfully hidden and protected itself for years, while secretly running a global megacorporation?
Why did the AI steal technology for rewriting human memories? Why is it holding four young gifted orphans in a hidden research facility? And why has it begun inexplicably crashing?
But when powerful entities reach out from the shadows, and a primeval land awakens to magic, things are guaranteed to get strange – deadly strange.
603 pages, Kindle Edition
Published December 11, 2025
3 people are currently reading
614 people want to read
About the author
L.J. Kendall
6 books34 followersL. J. Kendall is an Australian author who failed to drown on five separate occasions on Sydney's northern beaches. He worked in software R&D and communication, and had a long happy marriage to an adventurous mediaeval scholar 22 years his senior.
He believes honesty is the best policy, most people are good and kind, and, with luck, you get out of life what you put in. He writes and enjoys believable sci fi and fantasy where the characters drive the plot. He loves quirky outsiders, and after over 10,000 hours of roleplaying – opposing everything from cosmic horrors, to time-looped cannibal space-Nazis, to evil megacorporations – he reckons he’d be helpful in a zombie apocalypse.
Inspecting his double-stacked collection of 2,000 paperbacks and his teetering piles of 300 or so books-to-be-read, you’ll find his favourite authors, including Roger Zelazny, Wen Spencer, and Marjorie M Liu.
His favourite movie is probably The Fifth Element, or maybe Ponyo. Or Mr Right. Or Alita: Battle Angel.
His author website is A Toe in the Ocean of Books
He believes honesty is the best policy, most people are good and kind, and, with luck, you get out of life what you put in. He writes and enjoys believable sci fi and fantasy where the characters drive the plot. He loves quirky outsiders, and after over 10,000 hours of roleplaying – opposing everything from cosmic horrors, to time-looped cannibal space-Nazis, to evil megacorporations – he reckons he’d be helpful in a zombie apocalypse.
Inspecting his double-stacked collection of 2,000 paperbacks and his teetering piles of 300 or so books-to-be-read, you’ll find his favourite authors, including Roger Zelazny, Wen Spencer, and Marjorie M Liu.
His favourite movie is probably The Fifth Element, or maybe Ponyo. Or Mr Right. Or Alita: Battle Angel.
His author website is A Toe in the Ocean of Books
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Displaying 1 - 11 of 11 reviews
January 12, 2026
Loved this book.
Cold Heart is not about stopping an AI.
It is about whether identity, consent, and moral agency can survive in systems—technological or institutional—that no longer require them to function.
L.J. Kendall explores themes of identity, consent, guilt, and what it means to be human in a world where minds can be rewritten and machines can feel. The novel builds toward an inevitable confrontation between human agency and inhuman intelligence—one that will decide whether memory, selfhood, and free will can survive the cold logic of an ascending AI.
At the center is Leeth, a covert operative whose previous mission failed to stop the AI from obtaining Omega. Haunted by guilt and fiercely protective of humanity’s autonomy, she prepares to infiltrate Newtopia City, a vast, buried Antarctic metropolis controlled by the AI’s omnipresent CityNet. Antarctica’s hostile magical environment makes conventional surveillance impossible, forcing Leeth into dangerous, solitary action.
Running parallel is Bonnie Parker, a pole dancer with lethal combat skills and a hidden agenda, who becomes entangled in the fallout from the AI’s crash and the growing chaos it causes. Meanwhile, hackers and agents inside the Bureau uncover disturbing evidence of sentient code behaving like a living ecosystem—one that can feel fear, pain, and identity.
A third thread introduces a mysterious, angelic being—newly fallen into the human world—grappling with guilt, fragmented memory, and an instinct to protect humanity. Drawn to emerging crises and “heroes,” he intervenes subtly, healing and helping while trying to understand what he is and what he has done.
Kendall trusts his readers by not answering the questions, but making us think and ask questions. Excellent.
Cold Heart is not about stopping an AI.
It is about whether identity, consent, and moral agency can survive in systems—technological or institutional—that no longer require them to function.
L.J. Kendall explores themes of identity, consent, guilt, and what it means to be human in a world where minds can be rewritten and machines can feel. The novel builds toward an inevitable confrontation between human agency and inhuman intelligence—one that will decide whether memory, selfhood, and free will can survive the cold logic of an ascending AI.
At the center is Leeth, a covert operative whose previous mission failed to stop the AI from obtaining Omega. Haunted by guilt and fiercely protective of humanity’s autonomy, she prepares to infiltrate Newtopia City, a vast, buried Antarctic metropolis controlled by the AI’s omnipresent CityNet. Antarctica’s hostile magical environment makes conventional surveillance impossible, forcing Leeth into dangerous, solitary action.
Running parallel is Bonnie Parker, a pole dancer with lethal combat skills and a hidden agenda, who becomes entangled in the fallout from the AI’s crash and the growing chaos it causes. Meanwhile, hackers and agents inside the Bureau uncover disturbing evidence of sentient code behaving like a living ecosystem—one that can feel fear, pain, and identity.
A third thread introduces a mysterious, angelic being—newly fallen into the human world—grappling with guilt, fragmented memory, and an instinct to protect humanity. Drawn to emerging crises and “heroes,” he intervenes subtly, healing and helping while trying to understand what he is and what he has done.
Kendall trusts his readers by not answering the questions, but making us think and ask questions. Excellent.
February 9, 2026
This was a Goodreads Giveaway. Thank you!
Imagine if a sentient AI and a magical assassin had a baby, and that baby decided to build a secret lair under Antarctica. That’s Cold Heart in a nutshell.
I’m giving this a solid 4 stars because, honestly, any book that manages to blend high-tech memory-wiping with a protagonist who escaped an 'Institute for Paranormal Dysfunction' (relatable, honestly) is doing something right. Leeth is the kind of government assassin you’d want to grab coffee with—if you weren't terrified she’d been sent to erase your weekend plans.
The vibe is very 'cyberpunk meets a fever dream.' While the plot occasionally feels like it’s crashing faster than the AI in the story, the world-building is top-tier. I mean, a megacity two kilometers under the ice? In this economy? Iconic. If you like your sci-fi with a side of 'wait, is that magic?' and a lead character who is cooler than the South Pole, you should definitely check it out.
Minus one star because I’m still a little worried my own smart fridge is plotting against me now."
Imagine if a sentient AI and a magical assassin had a baby, and that baby decided to build a secret lair under Antarctica. That’s Cold Heart in a nutshell.
I’m giving this a solid 4 stars because, honestly, any book that manages to blend high-tech memory-wiping with a protagonist who escaped an 'Institute for Paranormal Dysfunction' (relatable, honestly) is doing something right. Leeth is the kind of government assassin you’d want to grab coffee with—if you weren't terrified she’d been sent to erase your weekend plans.
The vibe is very 'cyberpunk meets a fever dream.' While the plot occasionally feels like it’s crashing faster than the AI in the story, the world-building is top-tier. I mean, a megacity two kilometers under the ice? In this economy? Iconic. If you like your sci-fi with a side of 'wait, is that magic?' and a lead character who is cooler than the South Pole, you should definitely check it out.
Minus one star because I’m still a little worried my own smart fridge is plotting against me now."
December 9, 2025
I was given an early release to review this book. With that disclaimer out of the way...
Leeth is set out on a mission alone this time. No real backup if things go wrong, nobody at the institute to save her, she's on her own in Newtopia, the AI controlled city in Antarctica, to finish her job from the last book. While on her mission, she gets involved with rescuing a group of orphans who were brought here by the AI for it's own goals I don't want to spoil. At the same time she's away, events kick off back home related to her adventure far south involving a mercenary company, an angel, and a new threat released from confinement. And if that wasn't enough, Tezcatlipoca is growing impatient for sacrifices... Did you know that Antarctica has the most volcanoes on Earth? As is often the case with books from the Leeth saga, "when it rains, it pours" and this story is no different as danger seems to compound with each chapter.
Engineering nerds (like me) will enjoy this book that covers a lot of sci-fi topics like the AI subsystems that run the city of Newtopia, the climate control methods they used to restore the ice shelves of Antarctica and dissipate heat into the air, the geothermal power-plants that provide energy to the continent as well as South America, and so on. The author did his share of research while writing the novel. If you were a fan of the scientific material in the last book, you'll enjoy this one.
Leeth is set out on a mission alone this time. No real backup if things go wrong, nobody at the institute to save her, she's on her own in Newtopia, the AI controlled city in Antarctica, to finish her job from the last book. While on her mission, she gets involved with rescuing a group of orphans who were brought here by the AI for it's own goals I don't want to spoil. At the same time she's away, events kick off back home related to her adventure far south involving a mercenary company, an angel, and a new threat released from confinement. And if that wasn't enough, Tezcatlipoca is growing impatient for sacrifices... Did you know that Antarctica has the most volcanoes on Earth? As is often the case with books from the Leeth saga, "when it rains, it pours" and this story is no different as danger seems to compound with each chapter.
Engineering nerds (like me) will enjoy this book that covers a lot of sci-fi topics like the AI subsystems that run the city of Newtopia, the climate control methods they used to restore the ice shelves of Antarctica and dissipate heat into the air, the geothermal power-plants that provide energy to the continent as well as South America, and so on. The author did his share of research while writing the novel. If you were a fan of the scientific material in the last book, you'll enjoy this one.
December 21, 2025
I received a free copy of this book in return for a review.
There's a little bad news and a lot of good news from my reading of this book.
First, the bad news.
I felt totally lost when I started reading this book 2 in a series. There were so many names and titles and monikers attached to what seemed important back story. I thought I had to figure out who they all were and what had happened in volume 1 and was feeling rather frustrated. But I kept going.
OK, now the good news.
I didn't really need to fret quite so much. I was able to catch onto the most important connections and let the story pull me along. And I very much enjoyed the story.
I don't want to give any spoilers here, so I'll just say that each of the story threads is intriguing and the weaving together of the threads is well-done. It has an intriguing blend of magic plus tech plus AI - all delivered unpredictably. The characters were complex and nothing was obvious about them or their personal missions, which kept me engaged throughout.
But I will go back to volume 1 -- I want to know how the world I just visited actually evolved, now that I know where they're going. (So far.) 🤓
There's a little bad news and a lot of good news from my reading of this book.
First, the bad news.
I felt totally lost when I started reading this book 2 in a series. There were so many names and titles and monikers attached to what seemed important back story. I thought I had to figure out who they all were and what had happened in volume 1 and was feeling rather frustrated. But I kept going.
OK, now the good news.
I didn't really need to fret quite so much. I was able to catch onto the most important connections and let the story pull me along. And I very much enjoyed the story.
I don't want to give any spoilers here, so I'll just say that each of the story threads is intriguing and the weaving together of the threads is well-done. It has an intriguing blend of magic plus tech plus AI - all delivered unpredictably. The characters were complex and nothing was obvious about them or their personal missions, which kept me engaged throughout.
But I will go back to volume 1 -- I want to know how the world I just visited actually evolved, now that I know where they're going. (So far.) 🤓
Read
November 19, 2025L.J. Kendall has the eyes and ears for creating magic. His dialogue has spark, and his insight is not only creative but also piercing. His blend of technology, science, and fantasy worlds is fascinating. COLD HEART includes elements of magic, intrigue, and futuristic worlds, and contains vibes of Jim Butcher's The Dresden Files, (although, to my mind, with "Bob" being rather a sentient AI). The premise drew me in right away, although I think I could have benefited from reading book 1, or perhaps if a quick recap of previous events could be included in future revisions of COLD HEART, that would have been helpful. Bonus points given for some great hooks that helped the pages turn faster!
December 7, 2025
This is a high-energy blend of cyberpunk, magic, and thriller action which drops the reader straight into a world of sentient AIs, mages, shamanic weirdness, and a fierce young protagonist navigating danger on every front. The writing is fast, vivid, and cinematic, with sharp dialogue and strong momentum. Fans of gritty urban fantasy and sci-fi hybrids will find plenty to enjoy.
December 21, 2025
Thoroughly enjoyable!
I had the opportunity to read this book for free. Though I wasn’t familiar with the series, it was well crafted and had enough back references that it worked well as a stand-alone story. I will be going back to the start of the series because I enjoyed the characters, flawed, but compelling; and the plot is a stretch, but comprehensible. I want to spend more time in this dystopian, but hopeful, world.
Thanks to the author for a great yarn.
I had the opportunity to read this book for free. Though I wasn’t familiar with the series, it was well crafted and had enough back references that it worked well as a stand-alone story. I will be going back to the start of the series because I enjoyed the characters, flawed, but compelling; and the plot is a stretch, but comprehensible. I want to spend more time in this dystopian, but hopeful, world.
Thanks to the author for a great yarn.
Read
January 3, 2026Dear reader
(This is a note from me, the author)
If you've been following Leeth's saga, I must first apologise for taking five years to complete this book. It wasn't from lack of effort! Early on, I had five 'impossible' problems to solve in regard to the plot, but wasn't willing to compromise and just hammer the plot into submission. Every character had to be true to themselves, and everything had to make sense.
As I battled on, in 2023 and 2024 AI (the key plot element), suddenly became hot. After following its development for over 40 years, in 2010 researchers with fresh approaches started making genuine progress.
Which is a super roundabout way of recommending Cold Heart to readers who want a more nuanced view of AI, that looks further ahead than the next few years. Though I confess the rate of improvement after 2020 took me by surprise too.
Pitting Leeth against the true AI she uncovered, and sending her to the Antarctic to (somehow) kill it was a huge ask, even for her, so I knew the idea had potential. I just had to trust her.
I don't write my books according to a story structure, but just by the seat of my pants. I have ideas for what might happen, and know who is doing what in the background. I set the stage, then let the characters take control while I hang on for the ride while keeping you, the reader, in mind.
I especially love the ending for this book, but I'll say no more, and hope you decide to read it to see what Leeth discovers deep beneath the Antarctic ice, with her little helper...
L. J. Kendall, Jan 3 2026.
February 14, 2026
Interesting Characters, Great World-building, and a Satisfying Ending.
So much happens in this book!
I took my time reading and immersing myself in the world of the Tik Tek AI, shamans, and with the characters and intricate plotting and sub-plotting. This is my first exposure to Leeth and this world where science fiction and magic work together to create a landscape for the characters to fight against and to work with. The world (and its dangerous forces of nature) is very much its own character.
Kendall really knows how to write interesting characters I end up caring about, complex plots that make me think about the world, great action sequences that had me hooked, and a really satisfying ending. This book is well worth reading if you like characters who are challenged to do the impossible against all odds.
I can't wait to read what Leeth gets up to next!
So much happens in this book!
I took my time reading and immersing myself in the world of the Tik Tek AI, shamans, and with the characters and intricate plotting and sub-plotting. This is my first exposure to Leeth and this world where science fiction and magic work together to create a landscape for the characters to fight against and to work with. The world (and its dangerous forces of nature) is very much its own character.
Kendall really knows how to write interesting characters I end up caring about, complex plots that make me think about the world, great action sequences that had me hooked, and a really satisfying ending. This book is well worth reading if you like characters who are challenged to do the impossible against all odds.
I can't wait to read what Leeth gets up to next!
February 19, 2026
Leeth and AI
Kendall continues to explore a number of themes in this age of machines. Although there is a lot of technological discussion, this book as previous have done, explores human behaviour and the now added complication of machines that are most likely smarter than we are in a manner that is complex yet easy to follow.
Leeth is our vehicle into technology and the effects on human morality. No spoilers but her background has been complicated and yet her bent is towards humanity and thus protecting it where she can as best she can.
Is this a book for everyone? Hard to say but it is extremely well written with humour, facts and complicated relationships that draw on every genre. A good read.
Kendall continues to explore a number of themes in this age of machines. Although there is a lot of technological discussion, this book as previous have done, explores human behaviour and the now added complication of machines that are most likely smarter than we are in a manner that is complex yet easy to follow.
Leeth is our vehicle into technology and the effects on human morality. No spoilers but her background has been complicated and yet her bent is towards humanity and thus protecting it where she can as best she can.
Is this a book for everyone? Hard to say but it is extremely well written with humour, facts and complicated relationships that draw on every genre. A good read.
January 23, 2026
💯💯💯💯💯
This entire review has been hidden because of spoilers.
Displaying 1 - 11 of 11 reviews