Lucy is a spoiled brat accompanied by her mother Marion who makes her invite Junior to her 6th birthday party which is a costume party. While at her party, Lucy is mean to Junior after she caught him looking at her birthday presents, then her and her friends make him fun of him for being adopted, and bans him from coming to her magic show. Junior gets back at Lucy by destroying her party, starting with cutting one of the ropes to the happy birthday banner, then scares her after popping one of her balloons with his pitchfork, taking the sprinkler from the backyard into Lucy's room then turning it on causing water damage to the room, ruining a game of pin the tail on the donkey by making the child pin the tail on a woman, throwing all of Lucy's birthday presents into the swimming pool, taking a frog from the garden fountain & placing it in a bowl of punch, cutting one of the pigtails of Lucy's friends with Lucy watching, taking the pinata removing & replacing the candy with pickles, and replacing the candles on the cake with roman candles. As a result, the cake exploded all over everyone. In each scene involving Junior's antics, Lucy is seen throwing a tantrum.