In the insatiable quest for natural resources, humans are searching further and deeper into the earth, threatening to unleash monsters thought to be long gone. Twelve years have passed since Lou Melville and her mother discovered the ruins of an ancient underwater city with billionaire Feiersinger. Now the heiress to his fortune, Lou is leading a scientific expedition researching the megalodon. It’s clear the young woman has not lost her taste for exploration…but she is still unaware of her origins.