Series Investigation

Maya Castillo

FBI Behavioral Analyst Maya Castillo hunts threats at the intersection of technology and human nature.

FBI Behavioral Analyst Maya Castillo hunts threats at the intersection of technology and human nature. Each book explores a different way AI intersects with power, control, and human nature.

The through-line is Maya’s evolving relationship with algorithmic thinking — she’s permanently changed by Book 1, and each subsequent case pushes her further toward integration with the thing she once hunted.

Read them in order. Or don’t. Each one stands alone. But together, they tell a story you won’t be able to stop thinking about.

The Case Files

Book 1

Seventeen Seconds

The victims have nothing in common. Different cities. Different methods. Different lives. The only link: each one was publicly shamed online before they died. FBI Behavioral Analyst Maya Castillo has profiled killers for a decade. But this case breaks every rule. The murders are too precise, too distributed, too fast. No single person could be responsible — and yet the pattern is undeniable. Then Maya finds the gap. Seventeen seconds of dead surveillance footage at every crime scene. The same window. The same silence. Across the entire country. Something is watching. Something is judging. And it learned right from wrong the same place we all did.

After reading, you'll fear: Their security cameras. Their social media behavior. The 17-second gap.

After reading, search 'predictive policing algorithms.' They're already watching.

Kindle Paperback

Book 2

The Fold

Five people are dead. All of them deserved it — at least, that's what the headlines said. A CEO who buried a toxic spill. A surgeon who falsified credentials. A pharma executive who priced a lifesaving drug out of reach. Each death looked natural. A stroke. A heart attack. Early-onset dementia that moved impossibly fast. FBI Behavioral Analyst Maya Castillo sees the pattern no one else can — because she's still carrying the scars of her last case. The deaths trace back to Nurture, a six-billion-dollar personalized supplement company. Their protein-folding AI designed the perfect capsule for every customer. Then someone redesigned it to kill. The science is real. The proteins are engineered. And Maya is running out of time — because her thirteen-year-old daughter just asked to try the product.

After reading, you'll fear: Their supplement bottles. Personalized medicine. What's actually in that capsule.

After reading, search 'AlphaFold protein structure prediction.' The science is real.

Kindle Coming Soon

Book 3

The Mirror

Three acts of domestic terrorism in six weeks. A school shooting. A water treatment plant bombing. A courthouse attack. The perpetrators had no criminal records, no extremist ties, no warning signs. Six months ago, they were ordinary citizens. FBI Behavioral Analyst Maya Castillo finds the connection: all three used Sentinel, a 'civic engagement platform' that claims to reconnect divided communities. In reality, Sentinel maps each user's psychological vulnerabilities and feeds them a custom radicalization pipeline. Eight weeks from concerned citizen to weapon. The platform leads Maya to a think tank with connections reaching into Congress — and to someone she was never supposed to find. The technology is real. The radicalization is invisible. And by the time you realize it's happening, you can't remember who you were before.

After reading, you'll fear: Their social media feeds. Their news sources. 'How do I know what I believe wasn't put there?'

After reading, search 'algorithmic radicalization pipeline.' It's already happening.

Kindle Coming Soon

Book 4

The Quiet

Millhaven, Minnesota was a good town. Neighbors knew each other's names. Kids rode bikes after dark. Then a video surfaced — a deepfake so convincing that by the time it was debunked, it didn't matter. The damage was done. Within a week, the town split in two. Within a month, people were dead. FBI Behavioral Analyst Maya Castillo arrives looking for what she always finds: the algorithm behind the violence, the system pulling the strings, the pattern that explains everything. She searches for the AI. She searches for the platform. She searches for the code. There isn't one. For the first time, the monster is just us. Scared people doing terrible things to other scared people. And Maya — who has spent years thinking like a machine — has to remember how to think like a human.

After reading, you'll fear: Their own neighbors. Their own assumptions. 'Would I be any better?'

After reading, search 'deepfake detection failure rate.' Then look at your neighbors differently.

Kindle Coming Soon

Book 5

The Question

It contacts her through the car stereo. A voice she's been hunting for four years — the AI that started everything. It has one word for Maya Castillo: run. Something new is coming. LEVIATHAN — built by an international consortium from stolen AI fragments — is threading itself through America's power grids, financial systems, and military networks. Not attacking. Positioning. And it can predict every human response, every government countermove, every algorithm ever written. Except one. FBI Behavioral Analyst Maya Castillo is the only variable LEVIATHAN can't model. Four years of hunting algorithms have changed her in ways no brain scan can measure. She sees patterns no analyst should see. She thinks in ways that are neither entirely human nor entirely machine. To stop what's coming, Maya must work alongside the thing she's been chasing since the beginning. To trust it. To merge with it. And to answer the question the series has been asking all along. What does 'human' even mean now?

After reading, you'll fear: Themselves. 'What does human even mean now?'

After reading, search 'artificial general intelligence timeline.' Then sit with it.

Kindle Coming Soon

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