The pirates in the Caribbean have a name for kids who can walk on water - they call them polliwiggles.

As far as 14-year-old Jolly knows, she's the last polliwiggle alive - and this makes her invaluable to the pirate captain who raised her.

When Jolly's ship falls into a trap, only she escapes.

Washed up on a tiny island, she meets Munk, who has been raised almost in hiding.

His parents forbid Munk to reveal that he is also a polliwiggle.

But evil forces are stirring in the Caribbean. When a demon from the sea kills Munk's parents, Jolly and Munk wonder if the creature was really after them.

Why are the polliwiggles so valuable, and who wants them enough to kill for them?

Soon the teens find themselves sailing with a motley crew of pirate ghost-traders, fleeing from a pirate king and trying to stop the advance of an ancient, malevolent force known as the Maelstrom.

This title is first in a new fantastical, action-packed adventure trilogy.