Gil meets a pair of fish playing volleybubble, but when Gil learns Nonny doesn't know how to catch a ball and the guppies prepare for a game of fishketball, Gil tries to teach him. But can Nonny win the game?
Gil is on his way to school when he sees fish playing. One fish blows a bubble, and the other fish play until it pops. Gil asks if he could have a bubble and they give him one. He takes it to school. He shows the other guppies how to play before it pops.
They become amazed. Mr. Grouper tells the different types of ball games there are. Molly then sings a song about choosing the right ball. Deema starts to run a ball store.
Molly asks for a big blue basketball, but Deema keeps picking the wrong ball. She finally finds the right ball and gives it to Molly. For some reason, the crab gets the small blue basketball. Lunchtime arrives. Gil gets an apple, Oona gets a pizza, and Nonny gets spaghetti and baseballs.
The guppies are seen outside playing with balls. Gil grabs a dodgeball and throws it to Nonny, but Nonny just closes his eyes and misses it.
Gil picks up the ball and asks Nonny what happened. Nonny replies that he doesn't know how to catch. Gil tells him he has to keep his eye on the ball and throws it again.
Nonny doesn't catch it and firmly says that he doesn't know how to catch. Gil says Nonny also has to put his arms out in front of him. Gil picks up the ball again and tells Nonny that he is going to teach him how to catch. Nonny puts his arms out, Gil throws the ball, but Nonny misses it. Mr. Grouper catches the ball while Nonny sadly states that he will never learn how to catch the ball.
Mr. Grouper says that he will if he keep practicing, and Gil agrees to teach Nonny how to catch. Mr. Grouper then shows how to throw a ball through a ring of fish. Nonny calls it fishketball. Mr. Grouper then shows what else you can do with a ball. Deema then starts singing about playing basketball.
The guppies then go back outside. Deema and Oona pretend to be pirates playing with balls. They start playing with a football when a ballhog shows up. They invite him to play, but he just takes the ball away.
They decide to play soccer, but the ballhog shows up and takes it. They wonder if he knows how to share. They ask him and he says no. They show him how to share and end the story. Mr. Grouper has arranged the bubble guppies to play fishketball. Gil, Molly, Oona, and Nonny play while Deema and Goby cheer them on.
Gil asks Nonny if he remembers what to do, and Nonny says yes. They give each other high fives before playing. The little fish start swimming and the game begins. The announcer tells everyone that to win, one of the guppies has to throw the ball through the fish in order to score. Mr. Grouper tosses the ball to Molly while the fish swim by.
Molly passes to Gil and the fish swim by. He passes it to Oona and the fish create a circle. Oona throws it but she misses. Molly still says it was a good shot. She picks up the ball and passes it to the viewers. The viewers pass it to Gil and the fish swim by. The fish finally stop by Nonny. Gil throws it to Nonny. Nonny watches, puts his arms out, and catches the ball. He is amazed. The fish tell him to shoot the ball. He shoots, and he scores. Nonny wins the game. The other guppies run over and congratulate Nonny. Clam goes down to the field to talk to Nonny. He asks how Nonny won. Nonny says that he won by keeping his arms out and his eyes on the ball and that his friend Gil helped him. Clam says that was fascinating. The guppies have won and the episode ends.