Grampu takes Oobi fishing. Oobi learns a bit about patience and finally catches a fish. At first, Oobi is thrilled, but then he feels badly for the fish and persuades Grampu that they should set the fish free. Oobi and Grampu enjoy their special day together, regardless of the fact that they return home without any fish. — NickJr.com (source)
Oobi is in the kitchen with a coloring book and a crayon. Grampu walks in and tells Oobi that they'll spend the day together. He asks Oobi to guess what his plans are, giving hints about fish. Oobi guesses that they'll go fishing, and Grampu says he's right. He brings out a new fishing rod as a present for Oobi. They go to the pier, where Oobi spots a seagull and a buoy. Grampu shows Oobi his box of fishing tools and teaches him how to cast a fishing rod.
Oobi feels a tug on his fishing line and reels it in, only to reveal an old shoe instead of a fish. Oobi and Grampu laugh about it and learn about patience as they wait for a bite. An interview segment plays as they wait. It involves Uma asking a girl and her grandmother about their favorite pastimes.
After this segment, the scene cuts back to Oobi and Grampu. They sing a short song, "Oobi and Grampu", about how they like spending time together. They're interrupted when Oobi feels another tug on his fishing line. He manages to catch a fish and is ecstatic. However, Oobi feels bad for the fish and asks Grampu to set it free. Grampu is surprised, but he understands and throws the fish back. Oobi says he's glad that he didn't take the fish away from its home. He and Grampu hug while they watch it swim around.
When they arrive back home without any dinner, Oobi finds an old can of tuna from the store and offers it to Grampu. He laughs and accepts it. He then tells Oobi that he has another surprise for him. He takes Oobi over to the piano area, where he's framed the old shoe from earlier on the wall. Grampu says that he kept the shoe so they can always remember their day together. Oobi hugs Grampu again as the episode ends.