Because the high school was vandalized, Officer Kirk imposes a curfew. Richie suggests that they demonstrate against the curfew, get arrested, and fight it in the courts. While Richie, Potsie, and Ralph are in the restroom at Arnold's discussing their plans, the lights go out, and they discover they are locked inside after Arnold closes up for the night.
Marion, tired of the monotony of everyday house chores, decides to enter a televised dance contest. When Howard won't participate with her, she secretly enlists the help of Fonzie. Arnold unwittingly tells Howard that Marion has been at Arnold's early in the morning with another man, and Howard becomes suspicious.
Fonzie reunites with an old flame, Pinky Tuscadero, who is in town to perform motorcycle stunts at a demolition derby.
The gang organizes a surprise party for Howard and Marion's 20th anniversary as clips from previous episodes are shown.
The entire gang goes to Colorado to help Marion's Uncle Ben at his dude ranch. They have to come up with enough money in five days to pay off Ben's neighbor who holds a note on the ranch. They also will have to keep the ranch up and running.
Richie temporarily takes over a local newspaper's advice column but only tells Fonzie about it. Potsie and Ralph, in an attempt to solve their continuous bickering problem, write in to Richie's column. Richie, via the column, suggests they literally draw a line down the center of the room and for Ralph to stay on one side and Potsie on the other.
It's their 23rd anniversary, and Howard and Marion are angry at each other over a rate-your-mate test they took in a magazine. Richie, Fonzie, and Joanie have arranged for them to take a second honeymoon. Marion angers Howard even further when she wants everything to be exactly the same as it was on their first honeymoon.
Mork returns to 1950s Milwaukee to learn about relationships in this retrospective episode.