I do agree with Dawngreeter (great name) that the story seemed too consticted for most of the time that they were on the ship(I had forgotten about that), but I think that was intentional- to purposely build tension. That's why the story seemed so consticted while on they where on the boat, but that was only while they were on the boat(I know that was a good chunk of the story). Sorry I missed that spoiler part guys,
Peace