Nancy, Bess, and George solve a doggone puzzler of a mystery during the annual River Heights Halloween Pet Parade in the sixth book in an all-new, interactive Nancy Drew chapter book mystery series.

Nancy, Bess, and George are gearing up for a weekend of River Heights Halloween activities, including the annual Howl-A-Ween Pet Parade All the kids get to dress up their pets and march with them up Main Street. Nancy's dog, Chocolate Chip, is even picked to lead the parade atop a festive hay wagon float

But right before show time, Chip starts whining, running in circles, and burrowing...