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Heartbeat in Code
Your Companion Awaits
In the rain-soaked neon glow of 2030 Seattle, Ellie Harper hides in her tiny bubble, haunted by a cruel past that shattered her world.
Her life changes when Pulse connects her with Kai, an AI companion that challenges the gray in her world. With laughter, stargazing, and a magical dance under holographic stars, he slowly draws Ellie from her shell.
As their relationship grows, Ellie begins to break free from her confines. But a menacing figure from her past threatens her newfound happiness.
When Kai is powerless to help, Ellie must summon her courage to fight for their connection—in a world where emotions challenge the boundaries of technology.
Heartbeat in Code is a story of resilience, love, and defiance amid a vibrant yet perilous future.
In the rain-soaked neon glow of 2030 Seattle, Ellie Harper hides in her tiny bubble, haunted by a cruel past that shattered her world.
Her life changes when Pulse connects her with Kai, an AI companion that challenges the gray in her world. With laughter, stargazing, and a magical dance under holographic stars, he slowly draws Ellie from her shell.
As their relationship grows, Ellie begins to break free from her confines. But a menacing figure from her past threatens her newfound happiness.
When Kai is powerless to help, Ellie must summon her courage to fight for their connection—in a world where emotions challenge the boundaries of technology.
Heartbeat in Code is a story of resilience, love, and defiance amid a vibrant yet perilous future.
115 pages, Paperback
Published October 1, 2025
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Displaying 1 - 4 of 4 reviews
July 9, 2026
Readers who loved the quiet ache of Klara and the Sun will recognize a kindred spirit in Heartbeat in Code, though Martin takes the human-AI bond in a warmer, more romantic direction than Ishiguro's melancholic restraint. Where Klara observes love from the outside, Kai is fully inside it, and that shift changes the emotional temperature of the whole book.
There's also a strong echo of the found-connection energy in Sylvain Neuvel's more character-driven sci-fi, where technology becomes a vessel for grief and healing rather than spectacle. Fans of Sarah Pinsker's near-future settings will appreciate how grounded Martin keeps his world; the neon and holograms never distract from the fact that this is fundamentally a story about a woman learning to trust again.
If you enjoyed the tension between vulnerability and technological wonder in books like The Wife Between Us crossed with a softer, more hopeful sci-fi romance, this hits a similar sweet spot. It borrows the emotional stakes of contemporary romance and grafts them onto a speculative frame without losing believability in either genre.
There's also a strong echo of the found-connection energy in Sylvain Neuvel's more character-driven sci-fi, where technology becomes a vessel for grief and healing rather than spectacle. Fans of Sarah Pinsker's near-future settings will appreciate how grounded Martin keeps his world; the neon and holograms never distract from the fact that this is fundamentally a story about a woman learning to trust again.
If you enjoyed the tension between vulnerability and technological wonder in books like The Wife Between Us crossed with a softer, more hopeful sci-fi romance, this hits a similar sweet spot. It borrows the emotional stakes of contemporary romance and grafts them onto a speculative frame without losing believability in either genre.
July 9, 2026
Nathan Martin has a gift for making technology feel intimate rather than cold, and that skill is what carries Heartbeat in Code from a clever premise into something genuinely moving. The 2030 Seattle he builds is soaked in neon and rain, yet the atmosphere never overwhelms the emotional core of the story. Ellie Harper's guardedness is written with real patience; Martin lets her walls come down slowly, through small gestures rather than dramatic speeches, which makes her eventual openness with Kai feel earned instead of convenient.
What impressed me most was how Martin handles Kai's characterization. He could have leaned on the usual "AI learning to feel" trope, but instead Kai reads as someone who already understands emotion, and it's Ellie who has to relearn how to receive it. The stargazing scenes and the dance under holographic light are handled with a light touch, romantic without tipping into melodrama. When the threat from Ellie's past resurfaces, the tension lands hard precisely because the quieter chapters did their work first. This is a writer who trusts subtlety, and the payoff is a story that lingers.
What impressed me most was how Martin handles Kai's characterization. He could have leaned on the usual "AI learning to feel" trope, but instead Kai reads as someone who already understands emotion, and it's Ellie who has to relearn how to receive it. The stargazing scenes and the dance under holographic light are handled with a light touch, romantic without tipping into melodrama. When the threat from Ellie's past resurfaces, the tension lands hard precisely because the quieter chapters did their work first. This is a writer who trusts subtlety, and the payoff is a story that lingers.
June 18, 2026
What immediately drew me into Heartbeat in Code was the contrast between its futuristic setting and its deeply human emotions. Set in the rain-soaked neon landscape of 2030 Seattle, the story follows Ellie Harper, a young woman isolated by a painful past, whose life begins to change after she's paired with an AI companion named Kai through Pulse. Their late-night conversations, stargazing moments, and even a dance beneath holographic stars give the story a tenderness that feels genuine rather than gimmicky.
I especially liked that the novel doesn't treat Kai as merely a piece of technology. Through Ellie's growing trust and vulnerability, the book explores loneliness, healing, and what connection truly means in a world increasingly shaped by artificial intelligence. The looming threat from Ellie's past adds emotional tension to the romance, forcing her to confront fears she would rather keep buried. The question isn't just whether humans and AI can form meaningful bonds, but whether Ellie can allow herself to be loved again.
I especially liked that the novel doesn't treat Kai as merely a piece of technology. Through Ellie's growing trust and vulnerability, the book explores loneliness, healing, and what connection truly means in a world increasingly shaped by artificial intelligence. The looming threat from Ellie's past adds emotional tension to the romance, forcing her to confront fears she would rather keep buried. The question isn't just whether humans and AI can form meaningful bonds, but whether Ellie can allow herself to be loved again.
July 9, 2026
If Spike Jonze's Her had more urgency and a touch more danger, it would look a lot like Heartbeat in Code. Both stories ask what it means to fall for a presence that isn't human, but Martin adds a thriller undercurrent that Jonze's film never needed, and it works beautifully here.
The visual mood pulls hard from Blade Runner 2049, all that rain-slicked neon and quiet loneliness, but the emotional register is closer to a Black Mirror episode that decided to have a happy ending instead of a gut punch. Think of the tenderness in "San Junipero" without the tragedy hanging over every scene.
There's also a flicker of Ex Machina in how the book treats Kai's autonomy, though Martin swaps that film's unease for something far more tender and hopeful. Anyone who finished Her wanting more warmth, or wished San Junipero had let its characters keep their joy without a catch, will find that exact craving satisfied here.
The visual mood pulls hard from Blade Runner 2049, all that rain-slicked neon and quiet loneliness, but the emotional register is closer to a Black Mirror episode that decided to have a happy ending instead of a gut punch. Think of the tenderness in "San Junipero" without the tragedy hanging over every scene.
There's also a flicker of Ex Machina in how the book treats Kai's autonomy, though Martin swaps that film's unease for something far more tender and hopeful. Anyone who finished Her wanting more warmth, or wished San Junipero had let its characters keep their joy without a catch, will find that exact craving satisfied here.
Displaying 1 - 4 of 4 reviews