After an undersea lab conducting research on a rare jellyfish known as the blue medusa mysteriously disappears and a bathysphere harboring Joe Zavala is attacked by an underwater vehicle and left helpless on the sea floor, Kurt Austin puts the NUMA team on the case.

Years ago, an ancient Phoenician statue known as the Navigator was stolen from the Baghdad museum, and there are men who would do anything to get their hands on it. Their first victim is a crooked antiquities dealer, murdered in cold blood. Their second very nearly is a UN investigator who, were it not for the timely assistance of Austin and Zavala, would now be at the bottom of a watery grave.

Kurt Austin and Joe Zavala investigate the smoldering hulk of a NUMA research vessel in the Indian Ocean and soon uncover an audacious scheme to permanently alter the weather on a global scale, killing millions.

Kurt Austin, Joe Zavala, and members of the NUMA Special Assignments Team are called in to investigate after ships are destroyed near the Azores and they find themselves entangled in the ambitions of an African dictator who may have developed a weapon with extraordinary power.