The piranha–razor-toothed terror of the Amazon–attacking in swarms, stripping flesh off the bones of helpless victims in seconds. Piranha have never been successfully introduced into American waters...until now.

For centuries, legends have told of the Kraken - nightmarish, tentacled beasts, attacking ships, and devouring sailors. Now, they have arrived off the shores of Beach City. Researcher Travis Prescott has been hunting these elusive beasts for years. For reporter Ashley Wells, it is the story of a lifetime. For Professor Clyde Spencer, it is the culmination of a lifetime's search. And for the wealthy and connected Colin Mason, it is a new and deadly obsession. But for Beach City, it is the beginning of a nightmare. Sometimes legends are real.

Doctor Jack Wright runs the Venom Lab, keeping mambas, cobras, and vipers of all kinds. He risks his life daily, extracting toxins directly from the fangs of the most venomous serpents in the world. But after a break-in at the lab, dozens of these deadly reptiles have escaped into the surrounding neighborhoods.

Great White sharks lurk off popular beaches – killer crocodiles and man-eating pythons prowl the Everglades. But for Abigail O'Neil, raised on the swamp, the most terrifying monster was her own father – a black-market croc-farmer notorious for feeding unwary victims to his jagged-toothed pets. Growing-up privy to unspeakable horror, when Abigail finally fled home, she thought she'd left it all behind. But now someone is stalking her – and they know all her deepest, darkest secrets.

When the ragged group of castaways stagger ashore, they think they are saved. Instead, they find themselves prey. But they are not alone in this lost world – and dragons are not the only predators. Reptilian savagery gives way to human nature – primal instinct becomes betrayal and murder – and they will all soon learn that sins of the past are never truly buried. But the lost world knows no judgment – and survival knows no sin. The dragons wait for them all. And they're hungry.