StoryPrincess Peach is holding a party to celebrate the 30th anniversary of Mario's first adventure to defeat Bowser. Mario heads to the party, but while he moves towards the center of the Mushroom Kingdom, Bowser breaks into Peach's Castle and takes her away... again...and as usual, Mario has to go through 8 worlds to save her.
Mario goes through 4 of the 8 worlds before finally taking on Bowser. Before he is defeated though, Bowser uses an item that he sabatoged from the castle: the Time Portal Blaster. As he plunged into the lava, he fired the blaster and sucked Mario back in time.
Mario came out of the portal in a coma. When he woke up, he was lying on the ground level of Peach's Castle... 30 years ago! He also found something very reminiscent about the situation. Toad then came and explained the situation to Mario and he went to save Princess Peach from Bowser, just as he did 30 years ago...
Mario goes through 8 worlds and then finds a strange vortex. After Peach headed back to her castle, Mario jumped inside of the vortex and returned to the present. Luigi met Mario outside of the vortex and explained to Mario what had happened. However, as the brothers went to fight Bowser, the dark menace used the Time Portal Blaster to send the Mario Bros. back in time to Subcon. Luigi and Mario then worked together in order to return to the present. However, Wart, at the thought of meeting the Mario Bros. again, created more powerful foes and trickier areas.