20 Regarding Margie

Looking for a way to get easy money, Bart, Milhouse, and Nelson go around town spray-painting people’s addresses on their curbs and making them pay them ten dollars for the unsolicited service. It turns out to be a success, but after they add the “7” and the “4” to the curb of the Simpson house (742 Evergreen Terrace), Homer tells them that he will not pay, so they leave without finishing. Homer finishes it himself, but instead of adding a "2" he changes it to "74 OAKLAND A'S- BEST TEAM EVER".

The next day, the letter carrier delivers them the wrong mail, thinking that their address is 74 Evergreen Terrace. Homer accepts the mail and receives steaks from Omaha, and an invitation to a wedding, which he attends. Marge gets a letter claiming that she has won a contest from a magazine to which she does not even subscribe. Her prize is that a maid will clean the house for a day while she relaxes. Not wanting the maid to judge her, Marge cleans the house until it is entirely spotless, except for a small stain on the kitchen floor. She combines all of her different cleaners to combat the stain, but the fumes make her woozy and she falls and hits her head on a stool. When she wakes up in the hospital, it is revealed that she has amnesia and cannot remember her family.

When she returns from the hospital, the home environment quickly jogs her memory of her children, and she also recognizes Ned Flanders and Milhouse, but Homer is still a stranger to her, since there is something unpleasant about him that her memory is trying to block.

Homer tries to get her to remember him, but to no avail. He then tries to make her fall in love with him again, but only manages to disgust her, when he tells her that they made love for the first time on a miniature golf course, which Marge claims she would never do. Homer and Marge split up and Homer moves out of the house.

Patty and Selma excitedly take Marge to a speed dating event, and she meets a man who shares her interests. However, when Marge tells him that she has amnesia and three kids, he immediately leaves. Homer catches up with him and scolds him for leaving her, saying that she is the most beautiful and kind woman he will ever meet, but the man drives off. Marge then tells Homer that even though she may not remember him, he knows the most wonderful things about her. As they drive back home, Homer mentions beer, and she suddenly remembers him through his alcoholic tendencies.