Controlled vocabulary and short sentences make this a perfect chapter book for the beginning reader. The mystery element in the story is surprisingly well communicated by the author given the limitations imposed by a chapter book format for this age group. The illustrations are humorous and well executed. The story begins with Tabitha Twiddle being woken up by a strange sound one night. The Twiddles have just moved into their new house and cannot figure out what the tapping sound is. Is it the plumbing? Is it mice? Or is the house haunted as the neighbors claim? A well-written and enjoyable story.