Several things happen on the eve of the long weekend: Jars Kelly and her cousin Snook are accused of stealing some valuable gem stones from the local jewellers; strange lights are seen hovering above their town, Cray Bay; and the bumbling Quenton Quigley stumbles across a riddle that could lead them to a hidden treasure. To find out what the riddle means, an adventure full of mystery, excitement and intrigue, plus lots of twists and turns, begins.

It all takes place in a dense Tasmanian rain forest where Jars and Snook accidently meet an old Chinese prospector called Wu Han who has a secret - the secret of the riddle. That's when the fun begins. There is a race between their old enemies the Grimshaws, the smelly visitors from outer space known as The Collectors and the Kelly kids.

Why are The Collectors lurking in the forest and why is Wu Han so afraid of them?
Who will be the first to solve the riddle and find the treasure?
Why is their Headmaster in for a big surprise when school resumes after the long weekend?