Superstitious Fonzie would rather suffer from a toothache than admit he's afraid he may lose his cool-ness if the dentist should pull the tooth, until his pain interferes with his favorite past-time...kissing pretty girls!
After a trying day of doing favors for friends and an encounter with a blood-bank doctor, an under-the-weather Fonzie falls asleep on the Cunningham's couch while watching a horror movie and feverishly dreams that a mad scientist is after what makes him the Fonz...his cool!
Dressed as a bride and groom at the Jefferson High masquerade party held aboard a boat cruising Lake Michigan, Jennie Piccolo and Fonzie both say "I Do" in a wedding skit performed by their drunk host, Captain Singer, unaware that a ceremony performed at sea by a bona fide ship's captain may be the real deal.
Under pressure from cousin Fonzie, Chachi invites Joanie and her parents to his house for dinner to meet his mother, but worries that his eccentric family will embarrass him in front of the Cunninghams.
During a week-end at Potsie's uncle's hunting cabin, Fonzie is accidentally shot in the vicinity of his favorite jeans' back pocket; but accounts of the incident vary when the guys tell their stories to a small-town sheriff while the Fonz is treated in the local hospital's emergency room.
Potsie pressures Lori Beth for a date with her sophisticated roommate and gets an embarrassing job to pay his rent; Fonzie joins the Big Brother program and enlists Howard's help for "little brother" Joey's best-friend dilemma.
Roger and Chachi are thrilled when a star basketball player transfers to Jefferson High and joins the team. But the excitement changes to deep concern when the talented player leaves practice on his father's orders without offering the explanation - which Roger soon finds out - that he suffers from epilepsy.
A major university offers basketball star (but academic non-standout) Chachi a scholarship to attend their school. Fonzie is excited, but Roger and Howard not only fail to show the same enthusiasm, they become suspicious at the college's academic background.
The Fonz stands in for his best friend when the Cunninghams and the rest of the gang arrange a wedding by proxy for Lori Beth and Richie after Army red tape tangles the couple's efforts to get the bride-to-be to Greenland.
Joanie prepares a narrated home movie to send to big brother Richie's overseas army base to bring him up to speed on the gang's summer activities, her break-up with Chachi and Fonzie's reunion with his old gang, the Falcons.
Originally 2nd half in first airing,"continued" episodes in re-runs): Fonzie,after being called "normal" by a woman he's dating,is re-uniting with his old gang and they're confronted by rival gang "The Warmongers" at Arnolds to settle an old score. Meanwhile, Joanie is avoiding Chachi after discovering he had spent time with a girl at the lake while she was working there that evening. Lori Beth has revealed to everyone that,on her last visit to Richie in Greenland,has become pregnant with their 1st baby. Howard,learning that he's going to be a "grand-father" becomes ...
Misunderstanding rules the day when Roger discovers why pretty Mona Hildebrand won't date him, Marion uncovers one of hubby Howard's carefully kept courting secrets and Joanie gets flowers from a mystery man.
Joanie regrets agreeing to join a popular girls' club with friend Jenny Piccalo when the snobby club officers try to keep Jenny from passing the initiation ritual by altering it to include stealing a park statue.
While her parents week-end in New York and sister-in-law Lori Beth flies to visit faraway husband Richie, Joanie Cunningham must prove more than her babysitting mettle when she is challenged with both a sick baby nephew and a broken furnace.