It's been months since Tom and Polly's explosive quest to Dollar Island, but their fizzling adventures are far from over...With Shipley Manor harboured safe at home, Polly and Tom have been looking forward to helping Hopper Hawkins spread the Fizzle - a magical potion that brings happiness to all who experience it. But something else has been speading instead - a poisonous conspiracy involving the mysterious 'Rattler'. And when Hawkins' great grand-daughter disappears, Shipley Manor embark on an urgent voyage to find her. Through magical forests and across Arctic mountains the shipmates encounter super-slugs, dolphins with three tails and eight-legged monkeys. But when they finally meet the secretive 'Rattler' they discover more than they bargained for. The fate of the world hangs in the balance as Polly and Tom do battle one last time...