There are many different variations to this, the most popular seem to be the legend about a Dutch ship that sank off the coast of Cape of Good Hope in 1641

The Captain Van der Decken, feeling pleased about their latest trip was so deep in thought that he failed to notice that the ship was sailing into a fierce storm and only realised when he heard the screams of the lookout. Being a stubborn man he thought that would make it and refused to give up, swearing that they would complete the trip even if it took till doomsday.

So even to this this day especially on stormy nights it is said the ship and its captain can still be seen, but if you do see it is claimed that you are doomed.

People who have reported seeing it says it as a strange red glow which surrounds it.