Nonny meets a marching band with a duck problem. A duck is in the way and they can't play their instruments. But with a little whistle, and a little help from Mr. Grouper and the Bubble Guppies, Nonny learns how to lead the marching band!
Molly tries to say "its time for bubble guppies" when suddenly Gil goes marching by and around. He leaves and she retries, but every time she does so he keeps interrupting her. So she grabs the cymbals nearby and crashes them together in order to make him snap out of it and they both announce "it's time for bubble guppies!"
The episode begins as Nonny overhears music and goes to investigate it. He sees a Marching Band on the field playing music and claps for them when they finish. The snail leader explains how a marching band works. They then begin to play again but come to a quick stop when they're interrupted by a duck!
Nonny greets the duck as they begin to retry, this time in another direction but it simply happens again! Nonny suggests that maybe the duck wants to be in the marching band to and manages to get it away from the band. They thank him for the aid and then decide to just go and practice somewhere else. The ducks decides to follow them though but he has to get to class and heads over to the school. Nonny suddenly comes in marching and they question what he was doing. He begins to explain the many instruments he saw and Gil asks what sorts of instruments they play. Mr. Grouper decides to explain them, such as a Drum, Trumpet, and a big instrument that you blow into: The Tuba! Nonny tells the viewers that he wants to join a marching band then Molly sings: "The Band Plays On"
Gil goes to the Marching Mart. He wants to join the band and needs an instrument that'll keep him with a matching beat. Deema explains the brand of instrument he needs, then shows him some but he comments on how only one of them is the one he needs to band on. The drum!
He takes the instrument, then leaves while playing it. Oona then comes in and asks for an instrument that you must blow into and she sees one wind instrument out of three choices. A Trumpet, cymbals, or Xylophone. Oona then blows into it and Deema calls Gil back. Oona and Gil then proceed to play together and Mr. Grouper says "Lunchtime!"
Molly is describing instruments as Gil tries to play the Tuba, he's doing it wrong however and soon tries to blow it the correct way. But its still not playing so he tries looking into it when suddenly Bubble Puppy blows into it!
In class The Guppies are trying to play Marching Band but are noticeably out of order. Nonny comments on this and Mr. Grouper decides they must need a Conductor. Mr. Grouper mentions that you need more just to be in a Marching Band, when just blowing a whistle won't work. He explains that a Conductor needs to tell the band exactly what to do, and bring a whistle so that the band will follow directions and sound more organized. Deema then Sings the dance song: "Everybody March"
The guppies go outside to play, with Molly and Goby pretending to be Cowhands. Oona tells the story of two cowhands who must march the cattle to the nearby farm. They notice a wanted poster for the "Marching Bandit", who is on the loose again. Wanting to keep the cows safe and they plan to march the cows to the nearby farm. Suddenly the marching bandit appears! He demands Molly hand over her drum and he steals their cows.
In hopes of retrieving their cows, Molly and Goby go to hide. They plan to wait for the Bandit to fall asleep, then they'll march their cows away. Quickly he falls asleep and they quietly sneak on by. Molly suggests they keep a beat by clapping quietly. At first this works but Molly and Goby have to hurry up and clap in hopes of getting their cows to move faster! Eventually even faster!
Seeing the Cattle Ranch in the distance, Molly and Goby successfully manage to get the cows inside and closes the door to keep them inside. Suddenly they see the Marching Bandit surrounded by a bunch of rattle snakes! They offer to help and Goby points out that the Jail is nearby. And so they tell him to close his eyes and begin to clap in a rhythm and lead him into the jail. He demands to be let out, but they refuse until he promises to give back the drums and stop stealing the drums. They even let him march with them and become friends!
Molly pretends to march, only to see Gil once again trying to blow the Tuba. He decides to look in it again, but only after making sure Bubble Puppy stays still. While looking inside a small fish blows into the tuba! Nonny then comes by to tell them they're going to go see a real Marching Band!
The guppies head to the football field and Nonny mentions how excited he is. The conductor says Hi to him and then begins to play. It's then Nonny notices the duck about to get in the bands way, forcing them to suddenly stop again. Even more ducks begin to form and arrive!
The performance is then canceled because of all the ducks. Nonny suggest they may want to march and holding up his whistle the young guppy swims down onto the field. The announcer mentions this, he greets the ducks, and then begins to blow into his whistle. All the ducks suddenly come over while quacking in a rhythm and Nonny manages to conduct both the ducks and band, saving the day!
Everyone cheers as the episode ends...
Gil gives his Tuba a final try, but makes sure both the fish and bubble puppy stay still. He's very sure something is stuck inside and makes sure they stay still again. As he goes to look its then a duck suddenly pops out! As he returns however Gil and Molly laugh.