Dead Reef: Dark Tide. crimson tide series, #3

Kate Morrison thought she ended the terror at Dead Reef. She was wrong. Six months later, the creatures have spread across the world's oceans - each one more deadly than the last. One manipulates machines. Another alters living tissue. And the largest has begun displaying something far more terrifying than hunger: intelligence. Ambition. Strategy. Now aboard the Cassandra, a covert deep-sea operations ship, Kate leads a team of scientists and soldiers who can't agree on whether to study the creatures or destroy them.
But the debate may already be irrelevant. The monsters are communicating across vast oceanic distances, studying human civilisation, and preparing something that looks less like an attack and more like a takeover. In the Pacific abyss, the Alpha has found the wreckage of an alien ship - the origin point of everything. The vessel that programmed the creatures. The technology that could make them unstoppable.
If they finish what the ship started, Earth's oceans won't belong to us anymore. Dead Reef: Dark Tide is a pulse-pounding sci-fi thriller where evolution meets extinction - and the tide is rising fast. Perfect for fans of The Meg, Michael Crichton, and Sphere.