"Todd's ears are so clogged up he can't hear, but he doesn't want to miss school. His teacher, the ex-spy Mr. Merlin, is sure to have secret codes for the class to figure out and a new mystery for them to solve..."
When her dog Rover is accused of tearing up Mrs. Ruston's tomato plants, Noelle investigates with her friend Todd and finds long yellow hairs that may point to the real culprit.
