Dr. Markowitz thinks his days of deep-sea diving are over. He’s perfectly happy to let his apprentice, Dr. Applebaum, take over the mantle of the world’s number one deep sea explorer. But when Applebaum’s sub mysteriously vanishes on a dive into the very deepest parts of the ocean, the terrifying evidence that is left behind is enough to force Markowitz into one last dive. The last images that Applebaum’s sub sent up to the surface suggest there may be something monstrous down there, a deep sea fish beyond the size of anything Markowitz has ever seen in all his days of ocean exploration. And even more horrifying, those last images suggest Applebaum and his sub may have been swallowed alive. But if Markowitz doesn’t act fast, Applebaum won’t be alive for long.