Despite Rico's assurances that it is all part of the act, Joanie is upset over the mingling that occurs between Chachi and several young women after he performs at Al and Louisa's newly opened restaurant in Chicago.
The band has a big audition for a record producer, but Chachi's attitude causes Joanie to decide to attend her nephew's birthday party in Milwaukee instead of singing with the band.
Joanie notices a guy looking at Annette during a performance at Delvecchio's, and she and Chachi introduce Annette and the guy, Wendell. They quickly hit it off and decide to get married within three weeks of their first meeting. Prior to the wedding rehearsal, however, Wendell makes a pass at Joanie.
With nothing to do during the day, on the advice of Chachi, Joanie starts hanging out with her roommate who attends college. On behalf of the band, she accepts an offer from the fraternity to play at one of their parties. Chachi thinks it would be beneath them to perform at such an event and becomes resentful of Joanie's new life. Meanwhile, Al tries to get in shape.
The band is set to audition for a spot on Twist Fever when a woman tells them the show is looking for a band with a gimmick. When a family band is up next, the woman says that they are the type of gimmick the show is looking for. Joanie and Chachi claim that they are a family band with Louisa as their mother and visiting Fonzie as their father. Meanwhile, Al is upset with himself for not making more of an effort at being a true father to Chachi.
Howard and Marion come to Chicago to visit Joanie at her apartment after Chachi answers Howard's phone call late the night before. When they arrive, Chachi is there wearing Joanie's bathrobe and shower cap.
Joanie and Chachi argue about gender superiority. Chachi believes that, specifically, men are better than women at basketball, so Joanie challenges him to go one-on-one with her female friend who plays on the school's team. Meanwhile, Al faces possible tax evasion charges but swears he has paid them.
Joanie goes out for coffee with her art teacher. She says it isn't a date, but Chachi insists it is. He goes to Joanie's school to check up on her teacher and sees that he's a young blond. To avoid being seen by Joanie as she and other students enter the room, he tells the teacher that he is the model and soon learns that he will be posing nude. Meanwhile, Al wants to join the Chicago Leopard Lodge.
Louisa's friend from high school, Vanessa, who is a record producer, comes for a visit and asks the band to play for her. Mario suspects Vanessa is interested in Chachi for more than just his music.
After Joanie claims she saw Paul McCartney at the hospital while visiting a friend, Chachi and Annette go to the hospital to see for themselves and find a man who bears his resemblance. Meanwhile, Al is promoted to "Savage" in the Leopard Lodge, and Louisa doesn't want to go to the ceremony.
Against Louisa's wishes, Joanie and Chachi go to an exotic French film and try to leave when Al and Louisa show up to watch the same movie.
After repeatedly being warned about showing up late for and taking excessive breaks during performances, Al and Louisa are left no choice but to fire the band.
Faced with work to do for other classes, Joanie asks Mario to type her 30-page history paper for her. After he finishes it, Mario accidentally burns it on the kitchen stove. When her teacher hands back the graded papers, he notes that Joanie's and another student's are exactly the same. Meanwhile, Louisa gets an ugly couch, but Al can't bring himself to tell her.
After preparing a terrible stew for Chachi, Joanie daydreams about their golden years when he leaves her for a woman that can cook. Not wanting her life to mirror the dream, Joanie enlists the help of Louisa to make a great dinner for Chachi. Rico tells Chachi to say the dish is good even if it isn't.
On Christmas Eve, a night which Al wanted to spend at home with his close family and friends, Rico books the band to perform on the Christmas Radio Special. After stopping to pick up a hitchhiker on their way to the studio, their van gets stuck in the snow.
Chachi is convinced that Joanie will leave him when her first love comes back on the scene.
After seeing how much in love Louisa's Aunt and Uncle are after 50 years of marriage, Joanie and Chachi decide to elope.