You're one of many guests aboard the Triton Cruise. Mistakenly, the cruise takes a turn to the wrong direction, landing the everyone on board to travel deep within the Caribbean Sea. The Caribbean Sea had been under worldwide watch after many reports of aquatic tail-like parasites have been in the sea. The cruise had mandated a lock-in for every guest on board. Upon contact with one of the parasites, it will attach to tailbone of human, and slowly transforms them into an anthro shark.