After taking a tour of the National Bureau of Printing and Engraving, KC and Marshall find out from KC's stepdad, the president of the United States, that several stacks of $100 bills have gone missing. That's thousands of dollars--gone! KC is determined to track down the thieves, and her number one suspect is a woman named Polly, who works at the Bureau of Printing and Engraving. Is sweet Polly a criminal mastermind? Or is she just a pawn in a bigger plot to steal from the Treasury?