Harold is seven years old and can't tie his shoes. Not only can't he tie his shoes, he's completely and utterly convinced that he will never (ever) be able to tie his shoes. Second grade is two weeks away and he's worried that the kids at school will laugh at him if they know he can't tie his shoes. Harold and his mother and his father and his big sister Gina move into a new-for-them house, and in the garage Harold discovers the Wimple-Dimple Dimmer-Wimmer. Harold doesn't know what a Wimple-Dimple Dimmer-Wimmer is or what it does, but the more Harold gets to know "that pile of junk in the corner" the more interesting he finds it. Harold's got a lot on his mind, between trying to figure out what the Wimple-Dimple Dimmer-Wimmer is and trying to remember all the things his mother AND his father want him to do (take his shoes off every time he comes inside? Really? Every time?). But he still can't tie his shoes...or can he?