Mario is jumping up and down on an umbrella (which happens to be rather bouncy) while Luigi is inside the Crate Game building, trying to beat his record.
Mario: Boingy boingy boingy!
Luigi: Time!
Crate Game Pianta: 00:13:64, Luigi.
Luigi: Yes! See ya, dude.
CGP: Peace out.
Luigi: (just walking out) Yo, yo, yo, wut's da 411?
Mario: Oh no! The Crate Guy made Luigi talk weird again! Why that little...
Mario walks into the Crate Game building, pulling up his sleeve with his fist. After he gets in, screams of pain are heard outside the building.
Mario: (just walking out) Hey, Luigi, wanna go see how Noki Bay's doing now that it's clean?
Luigi: Okay.
Mario and Luigi hover to the other side of Delfino Plaza, head for the glow, look at the sun, scream "OW, MY EYES!!!", open their eyes, and see the water clean, the grandpa Noki, the grandson Noki, and a familiar purple Pianta head bouncing up and down on the cliffs.
Grandpa Noki: Oh, Mario, Luigi. We wanted to thank you for cleaning our bay.
Grandson Noki: And another thing: Do you know that guy up there? Me and Grampa have been watching him. When he first walked up there, he saw us first and told us to send you two up when you get here.
Mario: Uh...
Grandpa Noki: Well, you two better be on your way.
Mario and Luigi head up, and see II Piantissimo.
II Piantissimo: Ah-ha-ha! It is I, II Piantissimo! We meet again, foolish men! I offer you a Shine Sprite!
Mario: Really? Tha- what's the catch?
II Piantissimo: Race me to that flag!
Mario and Luigi see a flag on the corner of the bay.
Mario: Okay, we'll race you.
II Piantissimo: Ah-ha-ha! Very good! Are you at the ready? Then get set... GO!!!
II Piantissimo starts running but crashes into the edge of a platform.
II Piantissimo: Ah-ha-ha! I guess I will swim!
Mario: I'll swim, too, Luigi, okay?
Luigi: And I'll climb platforms.
Mario crashes into the platform, and Luigi climbs on it. Eventually, Mario catches up.
Mario: You're a slow swimmer!
Mario bumps II Piantissimo out of his way. II Piantissimo strikes back at him. They both end up doing this over and over and over and over and over... Meanwhile, with Luigi...
Luigi: (going from platform to platform) ... HEY! I'm going in circles! I still see it though... I guess I'd better hover to it. (Geez, I'm so stupid!)
Luigi starts hovering but he lets go of one of the handles on FLUDD2 and falls in the water. A fish falls in his face.
Luigi: Aah! I can't see! I can't see! I can't...
Crash!
Luigi falls near the flag.
Luigi: Ah! Just... a little... closer...
Meanwhile, Mario crashes onto the shore.
Mario: Ah! Just... a little... closer...
Mario and Luigi: !
Luigi throws Mario over to the flag.
Brothers: Yes!
II Piantissimo swims over.
II Piantissimo: *cough cough wheeze hack* My, you two are full of energy. *wheeze* Here's your Shine Sprite. *cough*
II Piantissimo throws a Shine Sprite to appear. It lands on Mario and he does the Shine Dance.
Mario: Yahoo!
Luigi: Onto the next Shine!