On a small island of the Louisiana coast, prospects for a better life grow fewer with each passing year. So, when a mysterious blood red pearl is discovered, John Hightower and his friends begin diving in search of more. Soon however, relationships are put to the test and lifelong friendships begin to unravel amid a flurry of betrayals, lies, and death.

While the drama plays out among the friends, something stirs in the sea; something that has lain dormant for centuries. A creature that has grown to an unimaginable size, with an appetite to match. An appetite... for human blood.

Should John and his friends somehow survive their mutual greed and paranoia, there is no guarantee that they will survive the monstrous creature that awaits them in the deep.