When Homer and Bart bump into Ned and Todd Flanders at the Miniature Golf course, Homer is convinced that his son could beat Todd in the upcoming miniature golf tournament. They both enter, and they place a bet on who will win - the loser having to mow the lawn in his wife's Sunday dress. Lisa researches and helps Bart, but when it comes down to the final, the pair give up and split the prize in half.
On a beautiful day, Homer is mowing his lawn. Ned Flanders invites Homer into his beautiful rumpus room to have some beer and club sandwiches. Homer accepts, but eventually protests against Flanders and accuses the Flanders family of having things better than the Simpsons do, and in a rare example of anger, Flanders asks Homer to leave. After discussing things with Marge, who reminds him that Ned is a perfect neighbor, Homer goes for a walk. Meanwhile, Maude Flanders suggests to Ned that he should try to patch things up with Homer, and he writes a note to Homer with humorous "Flanderisms" in it, after hearing from Reverend Lovejoy that the Bible says that a gentle answer turns away wrath. Homer doesn't take the note seriously, and he, Bart and Lisa laugh at it.
Later on, Homer takes Bart for a round of miniature golf at Sir Putt-A-Lot's Merrie Olde Fun Center, where they unexpectedly run into Ned and his sons Rod and Todd. Homer continues to have a bad attitude towards Flanders. Bart and Todd learn of a miniature golf tournament in a few days, with the first prize being $50, and they both decide to enter. Although Todd is very good at miniature golf, Homer is confident that Bart will win the tournament. Homer unsuccessfully tried to help Bart practice for the tournament, complete with putting a picture of Todd Flanders in Bart's room and making him stare at it angrily for 15 minutes every day. Lisa provides better help for Bart through her reading spiritual books that calm Bart's mind, and she goes to the fun center to help him practice. Homer, still angry with Flanders, forces him into a bet with him; the father of the boy "who does not win" the tournament will mow the lawn of the house of the boy who wins, in his wife's Sunday dress.
It is the day of the tournament, and Bart and Todd are both doing well, proceeding to the final round of the tournament. In an extremely close match, Bart and Todd each do well, and are tied by the time they reach the eighteenth hole. Bart and Todd are both nervous, so they decide they are equally good, and call it a draw. Because of the way the bet was written down, both Homer and Ned are the fathers of "boys who didn't win", so both Homer and Ned must wear each wife's best Sunday dress and mow each other's lawn (Homer namely didn't care if he had to suffer the humiliation, as he felt that as long as Ned was humiliated as well, he'll be fine with it). Ned actually enjoys the experience, much to Homer's disgust.