Mystery Inc. loves looking for clues...so when the Huntingstun Library sets up a sleuthing competition with a huge prize, they are determined to win--Scooby snacks aren't free, after all. But every time they're about to complete a level, Batman foils them!

Is he also vying for the prize? Does the Batmobile need an upgrade? Or are the teens tangled up in a master villain's master plan?