Legend has long spoken of the prehistoric monsters that silently glide through the waters surrounding Long Island in the Bahamas. Locals know that some areas are better left unexplored – Dean’s Blue Hole being one of them. Blue holes are found throughout the world and the number is growing. These expansive underwater caves call to divers, but remain largely unexplored. Cursed with a strange name and dying marriage, Tyde Gregory, plans a last ditch effort to save his relationship. Diving at Dean’s Blue Hole on Long Island seems to be the only thing Tyde and his wife, Wendy, can agree upon. As hope turns to horror, Tyde realizes that there are things far worse than a broken marriage.