The Springfield Elementary School Model United Nations club is going on a field trip. On the bus, Bart, Nelson, Ralph and Milhouse are playing a game by racing fruit down the aisle. Milhouse rolls a grapefruit that gets stuck under the brakes. When bus driver Otto attempts to press down on the pedal, it squirts juice into his eyes, causing him to lose control and drive the bus off a bridge.
Otto attempts to swim for help but ends up being swept away by the current. It is later revealed Otto is picked up by Chinese fishermen, who plan to use him for slave labor. The students – Bart, Lisa, Milhouse, Nelson, Lewis, Ralph, Martin, Wendell, Sherri and Terri – swim to a nearby tropical island. Bart tries to tell the children that being stranded on an island is just like TV where life is easy and cocktails are plentiful, comparing it to The Swiss Family Robinson, only with more cursing. Reality soon sets in when the island is found to be largely barren and the children lack survival skills. With no food found on the island and no adult supervision, the children rely on snack food retrieved from the sunken bus by Bart. They awaken the next morning to find the snacks all gone. Suspecting Milhouse because of his pot-belly and nacho cheese breath, the students put him on trial and he blames the loss on a mysterious island "monster".
Back at home, Homer discovers that Ned Flanders has his own home-based Internet business, Flancrest Enterprises. Homer complains to Marge that everyone except the Simpson family are getting rich off the Internet, and he wants a piece of the action, despite knowing nothing about it. He launches his own dot-com company, Compu-Global-Hyper-Mega-Net, which is later bought out by Bill Gates and his goons. Unfortunately, Bill Gates' "buying out" procedure is having his goons destroy Homer's office and break all of his possessions, stating that he "didn't get rich by writing a lot of checks".
During the trial held by the students, there is insufficient evidence to prove Milhouse ate all the food. Because of this, Bart, acting as judge, acquits Milhouse. The other students are not happy with this verdict and attempt to kill Milhouse. Lisa tries to stop the violence, but gets pushed by Nelson. Bart, angered by this, tells everyone to leave Lisa alone. The other students end up chasing Bart, Lisa, and Milhouse into a cave, where it is revealed that Milhouse's "monster" is actually a wild boar. On one of the boar's tusks is an empty bag of chips, revealing that it was the actual culprit in eating the snacks. Nelson apologizes to Milhouse for the misunderstanding, who reveals that he only took "two sandwiches and a bag of Doritos". The kids kill the boar and eat it (except for Lisa, who adheres to her vegetarianism and licks slime from a rock instead, since the slime is what the boar is feeding on to survive on the island). The episode concludes with a comically obvious deus ex machina ending, narrated by James Earl Jones: