King Koopa plans to capture Prince Hugo the Huge the ruler of Giant Land and turns Cheatsy, Big Mouth, Bully and Kooky into giants to do the job. It's up to Mario and Luigi to save the day.
The Mario Brothers are having a hard time keeping the kingdom stable while Toad and the Princess have fun in the sun in Hawaii.
Mario gets mistaken for a mummy's missing son, whose sarcophagus was stolen by Hip and Hop.
A Toadally Magical Adventure: Toad's mishandling of a magic wand belonging to the Wizard King of the West causes it to be taken by the Koopas. Misadventures in Babysitting: The Mario brothers accidentally emerge from a warp into a Brooklyn home. The parents mistake them for babysitters for their son, Junior, who somehow manages to enter the Mushroom Kingdom and along with Cheatsy, Kooky and Bully cause trouble for Mario and Luigi.
Oh, Brother!: After an argument, Luigi walks out into a rain storm. Mario tries to find him, only to get captured by King Koopa and Kooky. It's up to Luigi to rescue brother. Misadventure of Mighty Plumber: As King Koopa plots to rob Pipe Land, he brings the Mario brother's hero, Mighty Plumber, into the kingdom to distract them.
It's campaigning time when the Princess and King Koopa compete in an election that will decide the ruler of the Mushroom Kingdom.
Fed up with their dad, Kootie Pie and Big Mouth run away to Hollywood, where they use their magic wands to transform a monster robot into a real one.
Do the Koopa: The Princess hopes the Doom Dancer Music Box, which can create an endless dance spell, will put an end to the Koopas, but Mario and the gang's attempt to get it leads to it falling into King Koopa's claws. Kootie Pie Rocks: King Koopa kidnaps a band named Milli Vanilli so they can play for Kootie Pie.
Crimes R Us: The Koopas bust Crimewave Clyde out of prison and take him to the Mushroom Kingdom, where Clyde tries to teach the Koopa Kids about stealing. But the Mario brothers just seem to keep ruining their efforts. Life's Ruff: Hip and Hop steal a wand from King Windbag of Ice World. They turn the King and then Luigi into dogs, who have to pursue the twins through Miami to get the wand back and return to normal.
Up, Up, and a Koopa: Mario and Luigi rescue Emperor Ed of Sky World from King Koopa, but they get captured. So it's up Toad and the Princess to get on the Doomship and save the plumbers so they can handle Koopa's Raiser-Upper device. 7 Continents for 7 Koopas: King Koopa schemes for his Koopalings to take over the seven continents of Earth. Only the Princess, who was inadvertently brought aboard the Doomship, can stop them.
Mush-Rumors: A family inadvertently arrives from the real world into the Mushroom Kingdom. Everyone from the Mushroom citizens to King Koopa himself then hear rumors of invading aliens. The Ugly Mermaid: Mario and his frog suit gets turned into cement when he and the others defend the underwater city, Mertropolis, from King Koopa. Then Mertropolis' princess, Holly Mackerel, saves Mario from drowning and falls in love with him.
True Colors: Kooky and Cheatsy make a scheme to divide Mushroom people by painting them different colors. Recycled Koopa: When the Koopalings are forced to dispose of their garbage, they have it dropped on the Mushroom Kingdom and later Brooklyn.
The Venice Menace: Koopa gets another present for Kootie Pie - this time he plans to use his Doom Sub to chase everyone out of Venice, Italy then warp the entire city to Dark Land so Kootie Pie can have her own water park. The Mario Bros. are approached in Desert Land by an Italian gondolier and since Mario has a passion for the country of Italy, they couldn't resist. Armed with Frog Suits, can they stop Koopa in time? Super Koopa: Kooky has developed a pendant for King Koopa that will grant him the powers of the Mario brothers, but it can only be used in the real world. Koopa uses that to his advantage and lures his unsuspecting enemies into the real world using Luigi as bait. But the Princess manages to contact Toad, who races to get as many power ups to the Mario brothers in time.
