As you sit there talking about potential methods of escape the conversation is suddenly cut short as one of the other prisoners who was asleep begins convulsing and screaming on the floor. This goes on for several seconds, and as everyone looks on aghast, the colour begins to drain from the prisonerís skin. His screaming begins to lose intensity, and he stops thrashing. Finally, his body goes rigid, and his skin becomes the colour of ash, with one remarkable exception; a strange rune glows brightly on his forehead, then dims, until ultimately it fades to the same colour as the rest of the skin. You recall this individual having been acting strangely the last day or two.
If anyone has knowledge local they can make a roll to figure out what is going on with the guy. Knowledge nature to figure out why he had been acting strangely before now.
You are free to walk around, though the space is cramped with other prisoners. There is a steel lattice that keeps you locked in from the rest of the hold, and there is a man sized door in it, but it is kept locked. There is a bucket in one corner for waste which gets emptied by the cabin boy once a day, but he is accompanied by an armed sailor. So far, all attempts at conversation with them have been met with silence. Moldy bread is brought in daily as well. It's not very good, but they supply enough to keep everyone from going hungry.
Most of your possessions were taken away once you were imprisoned, including bags/weapons. You might have gotten away with a small object or two hidden in your clothes if you were lucky.