The Marvellous Land of Snergs is set on a fictional island somewhere on Earth, but difficult to reach. On the island is a colony of children (rescued from neglect by the redoubtable Miss Watkyns), the crew of the Flying Dutchman, and the Snergs, a race of short, thick-set, helpful people. Unfortunately Golithos, a not-so-friendly giant, and Mother Meldrum, a wicked witch also live there. When Sylvia and Joe run away for a big adventure their lives are in deadly peril when they fall into the clutches of these two evil characters. Gorbo the Snerg and Baldry the court jester come to the rescue.