Oobi and Uma go trick or treating. It is Uma's first Halloween, and after Oobi teaches her all the rituals, Uma takes Kako under her wing and helps him overcome his fear of Halloween. — NickJr.com (source)
Oobi is in his room, wearing a homemade dinosaur costume. He looks in the mirror and practices roaring. Uma walks over in a bunny costume. The siblings have each other guess what their costumes are meant to be. Oobi invites the viewers to guess along. Grampu appears and admires the costumes. He volunteers to take them trick-or-treating with Kako. Uma is really excited, since it's her first time.
They walk to Kako's house, where they talk with Kako's dad Papu. Papu gives the kids some candy, and Uma almost takes the whole bowl. Grampu explains that she's only supposed to take one. When Kako comes to the door, Oobi asks why he isn't wearing a costume. Kako unwillingly tells Oobi that he's afraid of Halloween and has never gone trick-or-treating before.
Uma tells Kako that she'll help him overcome his fear. She takes the tail of her rabbit costume and puts it on Kako's head, telling him that it's a snowball costume. The kids and Grampu walk over to Mrs. Johnson's house, where they hope to get candy. Along the way, Angus walks by in a ghost costume. Kako is terrified at first, but Uma shows him that it's just a costume and there's nothing to be afraid of.
When they arrive at Mrs. Johnson's door, Uma shows how to ask for a treat. Kako follows her lead and gets a box of raisins from Mrs. Johnson. She tries to guess what his costume is but can't get it right. She asks if it's a flower or a cotton swab, and Kako finally says that it's a snowball. After each of the kids gets a box of raisins, Oobi waves "goodbye" to the viewers and the episode ends.