The Simpsons sit on the couch as normal. From offscreen, someone hurls knives at the Simpsons’ heads, but only the walls are hit. Homer tries to get a bowl of chips, but a knife stops him, and slightly misses him.
Bart tricks Milhouse and Ralph into doing chores in the front yard. Sherri and Terri appear and introduce them to their "boy-crazy cousin who thinks Bart is cute" and they go to play spin the bottle in Bart's treehouse. Milhouse gets to kiss the girl, but she backs away and he accidentally kiss Homer. Homer strangles Bart over the use of a beer bottle Milhouse wanted to use (the beer actually landed "safely" into Homer's mouth, who drank it while napping), it lands them in the Simpson family court, with Lisa presiding as judge.
Marge, giving a testimony, tells the kids that when she was in high school, she had her first kiss with Homer, but Homer confesses that it was not his first kiss, giving Marge a huge shock. Homer recalls that when he was 10, he went to a camp for underprivileged boys, Camp See-A-Tree, where Homer meets Lenny, Carl, and as a counselor, Moe. It turns out the summer camp is more like a prison and they go to work in the kitchen at a rich girls' camp across the lake. Homer finds a retainer and returns it to the girl who lost it, though he cannot see her (they are separated by the kitchen wall). She wants Homer to see her later that night. He does so, even though due to an accident with a switchblade he is wearing an eye patch. He tells Bart and Lisa that she was the prettiest girl he had ever met until he later met their mother, but Marge admits that she was that girl Homer met, and if she'd known that he was that boy all those years ago then she never would have married him.
Marge gives her side of the story, saying that she was with Patty and Selma, Helen Lovejoy, Luann Van Houten and Cookie Kwan at their camp, "Camp Land-A-Man". At camp, Marge burns her hair with an iron by accident, turning it brown and she explains that is why Homer did not recognize her in high school. She meets Homer (who gives her a false name, Elvis Jagger Abdul-Jabbar) and they kiss, both fantasizing to the tune of "Happy Together" by The Turtles. They agree that the following night they will meet again, but Homer does not come. Marge mentions that she could not trust another boy for years.
Homer says he did not return for another date because he fell off a cliff into the lake and drifted to a fat camp, "Camp Flab-Away", which counted Mayor Quimby, Chief Wiggum and Comic Book Guy among its participants. The directors refused to believe he wasn't attending the camp and strapped him into an exercise belt machine for hours. Homer escaped the fat camp and made his way to Marge's camp, Marge had left the camp only seconds before he arrived. Marge's sisters told Homer that she hated him, and Homer said that what they had was special. Patty kissed Homer and asked sarcastically if that was special, to which Homer said no.
Marge now knows the truth and forgives him, but she thinks that Homer won't be able to preserve their love for long. Homer disproves it by showing his half of the heart-shaped stone, which he has kept through all the intervening years. Marge shows that she also kept her half (though for different reasons), and the two kiss until the light fades, while the two halves of the stone come together.