Our three heroes have to save a small fishing village in New Jersey from the encroachment of Bad Inc.'s killer big-city buildings and menacing skyscrapers.
Bad Inc. creates a forty-foot, monstrous Teddy Bear, named Binky, which terrorizes the city. The SUPER DUPER SUMOS must put the sumo-sized squeeze on Binky and save the day.
Booma's butt accidentally comes in contact with some of Bad Inc.'s evil shrinking solution. As his butt shrinks to the size of a normal man's, Booma loses all self-esteem. Kimo and Mamoo must get Booma up off the couch and out into the fight against a sea of monsters from Bad Inc.
In an attempt to see whose yak is the fastest, the big-bottomed bros enter themselves in the annual, world-famous Generic City Derby. In the race, they come upon Bad Inc.'s evil plan using a Trojan Horse to win and blow up the winner's circle where the Mayor of Tokyo and Wisdom San are gathered. It's neck and neck and turns out to be a photo finish in the home stretch of disaster.
The Super Duper Sumos must go undercover as ballerinas to thwart Bad Inc.'s evil plan to destroy centers of culture all around the world.
The Bad, Inc. boardroom becomes crowded with failed monsters and hideous experiments. They decide to build a new building...right on top of the Sumos' apartment! But, the big-bottomed bros aren't moving. Battles with animated toilets ensue, until the Sumos must battle the most hideous monster of all... their transformed Landlady.
A day at the beach for the Sumos turns into a battle against Bad Inc.'s evil plan to rid the world of cruise ships (which some would call a good plan). Our big-bottomed bros must fight mechanical sharks, giant squids and a motorized evil underwater compound shaped like a giant crab. But luckily, in the end, instead of being in deep sushi, they're eating it.
In a sumo-sized mix-up, the big-bottomed bros believe that Bad, Inc. has turned Prima into a small, glass figurine. They battle their way into Bad, Inc. to get Dr. Stinger to turn Prima back. But he can't. Instead he turns the figurine into a huge monster, which sets about smashing the city and spanking the Sumos' butts for fear of hurting "Prima." Luckily, Prima returns from her Spring Break vacation and the Sumos leap smash the figurine to smithereens.
The Sumos' yaks are stolen and our heroes don't know what to do without their transportation. They try to find them, and the police are absolutely no help. All the while, Bad Inc. keeps attacking. The Sumos must continue on the trail of their stolen yaks. It turns out the police had the yaks all along. Some of the boys were out joy riding. Go figure.
The Sumos take a break and go camping in the woods. At the same time, Bad Inc. has a company retreat in their toxic-waste plant nestled in the heart of the same pristine woods. All sorts of grotesque monsters attack the Sumos giving them no peace until the big-bottomed bros destroy the toxic-waste plant and send the bad guys packing back to the city.
Shemo, the fourth Sumoteer (separated in the first flashback of the first episode) arrives in Generic City bent on destroying Bad Inc. Shemo is tougher than our heroes, stronger, smarter, swifter... and she's a girl. This leads to sibling rivalry, which ends in a lesson well learned. She's a girl. No wait, it's something more along the lines of appreciating another's talents without being threatened or envious or something like that.
Bad Inc. blocks out the sun with a giant pie-shaped blimp in order to freeze the planet. The Sumos must put an end to this forever winter while fighting off robotic hockey players and a giant fifty-foot emperor penguin. The big-bottomed bros pop the blimp knocking the penguin out cold and turning up the heat for a grateful planet.