Living on a rundown shipwreck, Mr. Fish one day discovers an energetic young sea dragon Pip - who had mistaken his home for a junkyard - pilfering his belongings. The heated argument that ensues leaves both their houses in ruin. But there is hope! Embarking on a seemingly impossible quest to find the legendary 'Shimmer' to grant them a wish, there's only one problem: someone else is on the hunt...