On a normal cruise vacation ten teenagers go on a shore excursion in Mexico . They tour a cave and when the come out everything has changed.

The Sky has turned Crimson and every living thing as became crazed . They get back to their ship and conclude that the best bet is to get back to Miami where they started.

But on the way back they run into numerous problems and obstacle, From on and off the Ship. They must Band together to keep themselves and their Ship intact.