The episode begins with a UPS worker delivering a pokeball to Ash Ketchum. After delivering the (defective) pokeball, he is pleased to find that he only has one more package to deliver that day: one to the Mario Brothers from the Mushroom Kingdom. Unfortunately, Bowser is determined to stop that box from reaching the Brothers, and pays a Fed Ex worker to stop UPS.
Fed Ex confronts UPS, revealing that he is not only taking the job for the money, but also to humiliate UPS. By his logic, if UPS can't deliver something he loses credibility. If UPS loses credibility, he loses customers, and when UPS loses customers, Fed Ex gains customers. Realizing that Fed Ex is determined to make the world of package delivery his, UPS decides to stop his old foe.
After an epic brawl, UPS delivers the package to the Mario Brothers and returns home. Bowser, angry with Fed Ex, threatens him and warns him not to sleep.
Meanwhile, Mario and Luigi wonder what is inside the package, ending the episode with the series' first cliffhanger.
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