In the seventeenth century,<ref name="Alberge"/> pirate captain Ras Mohammed (Peter Boyle), accompanied by his incompetent Irish cook Dick Scratcher (Peter Sellers) and three crewmen, buries three chests of treasure on an unnamed island. Scratcher then kills the captain and three crewmen. He returns to the pirate ship and proclaims himself the new captain as only he knows the location of the treasure. He soon discovers his predecessor's treasure map was drawn in disappearing ink.