Ari is used to the chaos of living with a mad scientist mom, but her latest invention is about to cause a giant-sized problem! To help clean up the messy house, his mom tests out a brand-new gadget called a magnimizer, which is designed to shrink or enlarge absolutely anything. It sounds like a brilliant idea, until their grumpy neighbor, Mr. Jakes, accidentally gets zapped. Suddenly, Mr. Jakes is the exact size of a cockroach! To make matters much worse, a hungry mouse currently lives in their basement, and a tiny neighbor looks like the perfect bite-sized snack. Now, Ari has to jump into action, outsmart a ravenous rodent, and figure out how to operate the magnimizer to save teeny-weeny Mr. Jakes before he becomes mouse food.