Homer, Bart and Lisa react with horror when they realize Marge has cleaned out the attic and is giving away some of their useless possessions to Goodwill. Homer manages to save the "precious heirlooms" from the back of the Goodwill truck. Later, Marge remarks that many of the items, such as a pair of skis, have never been used.

Impulsively, Homer arranges for the family to go on a skiing trip. Fearing injury, Marge takes refuge at the ski lodge lounge. But her precaution proves futile: a large clock inside the lounge falls off the wall and breaks her leg. Marge is rushed to a hospital, where Dr. Hibbert informs her that she will be bedridden until the injury heals. Marge insists that she cannot be confined to a hospital, as there is too much housework to be done. But Lisa counters that she is perfectly capable of substituting during her absence.

At first Lisa seems able to manage with the chores. But Homer and Bart’s lazy, childish habits soon take their toll. As Lisa tries to sleep one evening, the sound of the I Love Lucy show emanates from downstairs. She pleads with Homer to turn down the volume, but he refuses.

A short time later, Lisa encounters the ghost of Lucille Ball. Lucy suggests a scheme that will "teach those slobs a lesson." Lisa embraces Lucy’s suggestion. She mixes green paint with oatmeal and dabs the concoction onto Homer and Bart’s faces as they sleep. When the pair awaken the next morning, Lisa convinces them that exposure to unsanitary conditions has caused them to contract leprosy.

Panicked, Homer and Bart turn to Ned Flanders for help. Flanders realizes that the family is ill-equipped to heal lepers. He arranges for Homer and Bart to travel to "a better place." Later that day, Lisa receives a phone call from Moe, who worries about Homer’s absence from the bar. Lisa realizes that her father and brother have both disappeared.

A short time later, a recuperated Marge walks into the house. Lisa relays the bad news: she tricked Homer and Bart into thinking they contracted leprosy, and now both have vanished. Flanders tells the pair that he paid for Homer and Bart to fly to Hawaii, where they are undergoing treatment at a leper colony.

Marge and Lisa journey to the island, where they discover Homer and Bart lying on the beach wearing swimsuits and sunglasses. Both Homer and Bart are fully aware that their sores were phony. But they decided to stay on the island and enjoy their free Hawaiian vacation …despite the often painful medical treatment they must endure.