A former rival of Fonz's, "Rico", shows up in town after 3 years wanting revenge. Fonzie, however, has promised Al's twin brother, Father Delvecchio, that he'll not fight for 1 day. But When Joanie and a sailor (plus Richie and the guys) end up cornered at a waterfront bar by Rico and his men, it's up to Fonzie to save them but at the same time keep his word. When mystery lady Kat Mandu steps in, Fonzie just might be able to do that.
—happipuppi13