New York Times bestselling author Mira Grant takes us on a terrifying journey into the unknown where human frailty meets the awesome power of nature and myths come to life.

"A claustrophobic, deep-sea terror tale that will leave readers glad to be safely on dry land." -Kirkus Reviews

"Absolutely delivers on beastly terror." -Vulture

The ocean is home to many myths ... some are deadly ...

Seven years ago the Atargatis set off on a voyage to the Mariana Trench to film a mockumentary bringing to life ancient sea creatures of legend. It was lost at sea with all hands. Some have called it a hoax; others have called it a tragedy.

Now a new crew has been assembled. But this time they're not out to entertain. Some seek to validate their life's work. Some seek the greatest hunt of all. Some seek the truth. But for the ambitious young scientist Victoria Stewart this is a voyage to uncover the fate of the sister she lost.

Whatever the truth may be, it will only be found below the waves.

But the secrets of the deep come with a price.