Ralph no es un ratón común. A él le encanta el tumulto de la ciudad. Por eso, Ralph suele pasar al otro lado de la pared del cuatro del hotel donde vive con su familia para buscar aventuras.
Ralph, an energetic young mouse, is tired of life at the Mountain view Inn. Over the Fourth of July weekend a boy named Keith gave him a mouse-sized motorcycle, but since then nothing exciting has happened. Hoping to find adventure, Ralph hops on his motorcycle and zooms away to the summer camp down the road. There he envisions fun, freedom, and delicious crumbs from peanut-butter-and-jelly sandwiches. Instead he runs headlong into a strict camp watchdog, a mouse-hungry cat, and even more fur-raising escapades. Suddenly home doesn't seem like such a bad place to be.
When Ralph and his pesky cousins accidentally make a mess at the Mountain View Inn, Ralph decides that he'd better take his motorcycle and leave. He persuade his young pal Ryan to take him to school, where Ralph is an instant hit with Ryan's classmates. But Ralph doesn't like being told what to do. Worse than that, his precious motorcycle gets broken.