American crook Renzo Capetto sees a chance to make a bundle when a Caribbean island has a revolution. He plans to help loyalists (and the national treasury) escape on his boat, then kill the men and blame their deaths on a mythical sea monster. Trouble ensues when the _real_ monster shows up!
I cannot overstate the sheer wonderful bizarreness of this movie. Corman had it written and filmed while they had a few days to spare after finishing another, and the end result is... It really is... I'm speechless. The quote at the top is from the narrator. The rest of the script is on about the same level.