His friends are baffled when Fonzie refuses to speak in his own defense after he is accused of manhandling a student and brought before the school board's disciplinary court.
Howard's fear that wife Marion's former college boyfriend will sweep her off her feet when he comes to the Cunninghams for dinner turns to shock when the man instead shows interest in...daughter Joanie!
Fonzie tries to help his cousin unleash his inborn "Fonzarelli Power" when Chachi decides to start dating again after his break-up with long-time steady, Joanie Cunningham.
Fonzie begins restoring a wrecked 1955 Chevrolet convertible, unaware it comes with more than just broken seats, a broken engine and a rusted shell. It comes with a beautiful young woman, to whom there's more than meets the eye.
Joanie says "yes" when Chachi pops the question and Fonzie finds that being single is a major snag when he decides to adopt Danny, his little brother from the Big Brother program.
Joanie primps and Chachi nervously paces as their family and friends gather on their wedding day, while Fonzie and Howard try to convince a by-the-book adoption administrator that some rules are meant to be broken.
Howard's poker game with the guys unexpectedly takes a not-so-friendly turn and Marion struggles to please her overly-critical mother when the Cunninghams spend a rare week-end apart.
Suffering from song-writer's block, broke Chachi is too embarrassed to tell his friends when he takes a job as a senior citizen dance instructor to make ends meet.
Fonzie, Roger and Chachi soon regret agreeing to help Howard Cunningham save his Grand Poobah position by becoming new Leopard Lodge recruits when they find out their pledge master is prankster Potsie "Sabu" Weber.