Dead Reef: Blood Tide (The Crimson Tide Series Book 2)

Marine biologist Kate Morrison came to Dead Reef to study coral formations. She found something studying her instead.
The local fishermen have stories about the blood tides — when the water runs red, and boats don’t come back. Kate thought they were superstitions. Then the attacks began.
Something ancient is rising from the trenches beneath Dead Reef. It has been down there for over a century, evolving in darkness, growing stronger with every kill. It’s not just hunting. It’s learning — cataloguing human behavior, human technology, human fear.
The lighthouse keeper’s family has kept a secret for four generations: the creature was chained beneath the reef in 1870 by a sailor who knew he couldn’t destroy it. Now those chains are breaking.
Kate has already lost one person she came here to protect. She won’t lose anyone else.
To stop what’s rising, she’ll have to go down into it. And in the crushing dark beneath Dead Reef, she’ll discover that the creature isn’t just what humanity has never faced before.
It’s what humanity created the conditions for.
Dead Reef: Blood Tide is a pulse-pounding creature thriller for readers of James Rollins and Andy Weir — and for anyone who has ever wondered what has had a century to grow in the dark.