It's Halloween night, and Witch Hazel is concocting a batch of witch's brew. As she goes about her business, she pauses at her magic mirror and asks it who's the ugliest one of all. The genie in the mirror replies that she, Witch Hazel, is the ugliest one of all. Hazel explains to the audience that she's "deathly afraid" of getting prettier as she grows older, a fear that she initially just laughs off.
Meanwhile, Bugs Bunny is out trick-or-treating dressed as a witch, his face hidden by an ugly green mask. He calls on Witch Hazel, who, seeing his costume, mistakes him for an actual witch. After making a comment about Bugs' appearance ("Isn't she the ugliest little thing?"), she dashes to her magic mirror and asks it a second time who's the ugliest one of all. The genie in the mirror looks towards Bugs, also thinks he's a witch and replies that he actually finds Bugs far uglier.
The jealous witch then hatches a plot: she invites the disguised Bugs in for tea, and prepares a potion containing an assortment of beauty enhancers. Bugs is about to drink the tea when he remembers that he's still wearing his mask and takes it off. Seeing that her "rival" is a rabbit, Witch Hazel dashes off to consult her cookbook. Sure enough, one of the ingredients for the brew she was making earlier is a rabbit's clavicle.
While she's gone, Bugs suspects there's trouble afoot and makes to leave, but he's stopped by Witch Hazel brandishing a meat cleaver. Bugs flees, with the cackling witch chasing him throughout the house. She dashes to her magic broom closet to grab her flying broomstick to keep up with him, but instead she mounts her magic sweeping broom by accident. The broom starts sweeping the floor with her clinging to it until she lets go. As Bugs hides, Witch Hazel finally traps Bugs using a carrot on a fishing rod.
Back at her cauldron, Hazel prepares to kill Bugs and use him in her potion. She's about to bring her cleaver down on the trussed-up rabbit, but he plays to her sympathies, gazing back at her with tear-filled doe eyes. Overcome with mercy, Witch Hazel bursts into tears, saying his innocent face reminds her of Paul, her pet tarantula. Bugs tries comforting her by bringing her the cup of beauty elixir disguised as tea, which she unknowingly drinks. Hazel instantly changes into a well-contoured redheaded beauty (a caricature of what Hazel's voice actress, June Foray, looked like at the time) as Milt Franklyn strikes up "Oh, You Beautiful Doll" in the background. Being a witch, Hazel is horrified at the prospect of becoming young and beautiful, a fate worse than death.
Hazel dashes to her magic mirror a third time and meekly asks the genie (in a softer, sexier tone of voice) if she's still ugly. Upon seeing Hazel's new appearance, the genie gives a very Bob Hope-like "ROWR, ROWR!", immediately falling in love with her, and lunges to grab her. Hazel then flees on her actual flying broomstick, with the genie slowly gaining on her with his magic carpet. Bugs, who's still at Hazel's house, promptly calls the local air raid headquarters to report "a genie with light brown hair chasing a flying sorceress!".