The family is celebrating by having brunch at a fancy restaurant; Homer has finally paid off the mortgage. Lisa and Bart get into a food fight, embarrassing Homer. Homer goes to Moe's, where a visit from the health inspector, results in his death from eating one of Moe's pickled eggs. The new health inspector comes down hard and Moe's is closed until the violations are cleared up. The regulars hold an Irish wake for the demise of Moe's.
Homer decides to help Moe reopen his bar; and he gets a new mortgage for their home. When Marge finds out, as a new co-owner she goes with Homer to the bar and tells Moe that there are going to be changes until he pays them back. On Homer's next visit, he finds Marge behind the bar, protecting their investment. She sends him home to take care of the kids, while she sells Moe on the idea of remodeling the place into an English pub. The new place opens and is a success; the kids tell Homer that they've noticed that Marge is spending more time at Moe's than he ever did. Homer becomes worried; but Marge tells him there is nothing to worry about.
They go to a movie together, but they are joined by Moe. Homer is more worried than ever; Lenny and Carl tell Homer that Marge and Moe are having an emotional affair. When Marge and Moe are leaving to go to a convention together in Aruba, Homer makes a mad dash to the airport and gets to the airplane as it is taxing down the runaway. He confronts Moe, but Moe makes him realize that he really doesn't know that much about his wife. Homer concedes defeat, but Marge tells Moe that she doesn't love him. She tells Homer that she is totally committed to him.
In Aruba, Marge makes Moe realize that he might be able to make a woman happy some day with a few changes. Marge realizes that no one is home watching the kids, but the kids aren't at home as Bart has them entered in a European balloon race.