In the intro, supposed emissaries from the Bean Bean Kingdom visit Princess Peach of the storied Mushroom Kingdom under the guise of gift-giving. Unfortunately, it's a trick and Ms Peach gets blasted in the face with a billowing cloud of green smoke. As the terrified guards (who are supposed to protect the Princess) rush for the exits, the two "henchman" rob the Princess of her voice and spirit themselves away.

Scene Shift: Luigi is hanging clothes and Mr. Toad rushes in, yelling and hollering that there's an Emergency. Toad decides that Mario should be summoned and runs into the bathroom...only to catch an eyeful. The sight is apparently too much for Toad's optic nerves to accept and he hurtles out of the bathroom and runs right into a drawer. Mario soon emerges from the steamy room, slightly naked and rouses Mr. Toad from his self-inflicted coma. Mario is soon apprised of the situation and he jumps onto the drying clothes outside and drags Luigi with him to the castle...

Bowser's already there on a kidnapping mission and the Princess is welling out the waterworks but a battle ensues where Mario and Bowser face off. After Bowser is laid to waste, he sputters, stammers and claims that this is no time for fighting. The Princess' voice has been replaced with a bomb-laden vocabulary where everything she attempts to say becomes bombs that rain down. To restore order and to make the Princess suitable for kidnapping, Bowser agrees to join Mario and Luigi (well, Luigi is taken by force) in a quest to retrieve the Princess' voice before her bombastic utterances level the kingdom.

A bonus game in the cartridge is the classic Mario Bros arcade game where Mario or Luigi bop turtles, crabs and other creatures from below.