The Mushroom Kingdom has been plagued by a mysterious malady dubbed "the blorbs!" Citizens far and wide report of their friends and loved ones ballooning to blimp size, then rolling away out of control at an alarming rate. Princess Peach™ and her cohorts enlist Mario™ and Luigi™ to set out and find the cure.
The burly, surly villain known as Bowser™ storms the castle, determined to abduct the princess--only to be thwarted by the brothers once again. Determined to have his revenge, Bowser stumbles upon a shady travelling merchant who offers him a Lucky Shroom. This freaky fungus promises beefed up powers to let Bowser take down Mario once and for all.
Bowser scarfs down the mushroom, only to come down with a strange affliction that causes him to inhale everything around him! Stumbling to Princess Peach's Castle in this volatile state, he manages to swallow Mario, Luigi, and the princess whole thanks to the uncontrollable powers of the Shroom.
Do the Mario Bros. have the intestinal fortitude to save Princess Peach, and avoid being digested like yesterday's lunch? Will the citizens of the Mushroom Kingdom rid themselves of the Blorbs?