They were designed to save American agriculture. They were designed to think together.
Now they're designed to hunt.
When Silicon Valley biotech startup Corvus Biosystems releases millions of engineered super-corvids into California's Central Valley, the birds do exactly what they were built to do: eliminate agricultural pests, boost crop yields, and make shareholders very rich.
Then the Sentinels develop collective intelligence. Then they form murmurations. Then they start targeting humans.
Dr. Mira Vasquez helped design them. She warned her employers that the birds' engineered cognition would evolve beyond control. She was paid to keep quiet. Now her 10-year-old daughter is trapped in a besieged summer camp 200 miles south, and Mira is the only person alive who knows how to shut the birds down.
Armed with a stolen kill-switch frequency, a father's shotgun, and the guilt of a woman who should have been louder the first time, Mira must cross a Valley ruled by forty million coordinated predators - and then hold a mountaintop tower for ninety minutes while the sky falls.
MURMURATION is the third book in Nora Penn's creature-horror series. If you liked Jurassic Park, The Birds, or Annihilation, this is the book you've been waiting for.