When the crew is on an everyday voyage on the Nomad, they come across four sailors stranded in the middle of the sea.  It doesn't take long until they discover that the sailors are in a huge mess of trouble, and unfortunately Sinbad and his ship get into the middle of it when they take the sailors aboard.  It turned out that Fontassel, the captain they picked up, had killed one of Posiden's sirens for a reward, and Posiden was seeking vengeance against the wrongdoing.