At school, Miss Skullnick gives an algebra lesson as her students look bored. Star is the most bored among them, lying in her seat with her feet on her desk. She notices the class hamster "Marisol" looking equally bored in her cage and sets her free out the classroom window. Because of this, Miss Skullnick gives Star detention and orders Marco to bring back Marisol.
When Star is dragged to detention, she meets Janna and three other students: Serge, Ingrid, and Toby. Frustrated with being cooped up in classrooms, Star attempts to escape by using her magic wand to create an escape window. Janna stops her, however, and tells her she has been elected "Mayor of Detention" which Star questions the legitimacy of since she arrived just moments ago. Janna explains that, as the "mayor", it is Star's duty to address the needs of her "townspeople". Reluctantly, Star agrees to fulfill the requests of some of her fellow detainees. She gives Serge some candy from under a desk, Janna a tattoo on her left arm, and Ingrid a cone when in fact she wanted a guillotine so she can decapitate her teddy. The last request comes from Toby, who explains that he and the other kids in detention get together to watch wrestling on a television across the hall using a stolen TV remote. Unfortunately, the remote's batteries are dead. As Star wonders where to find fresh batteries, she hears Oskar playing his keytar outside. Since Oskar's keytar uses batteries, Star suggests they get some from him. Meanwhile, Marco finds Marisol in a drainage pipe and gets his arm stuck trying to get her out.
Janna comes up a plan for her and Star to sneak out of detention and reach Oskar in the parking lot, but she says they have to be back before 1:00pm when Miss Skullnick checks in on them. Together, Star and Janna get past the janitor's wet floors, blend in with band practice; the last obstacle between them and the parking lot is Miss Skullnick eating lunch on a bench. Star suggests they blast her away with a bazooka, but Janna chooses instead to scare her off with a snake in a can of potato chips. Star places the can next to Miss Skullnick, but before she can even open it, she is drawn away anyway when Marco causes a commotion with his pipe-trapped arm. With Skullnick out of the way, Star and Janna reach Oskar in the parking lot. Before Star can ask him for batteries, she becomes incoherently lovestruck upon seeing him, so Janna asks instead. Oskar says he needs his batteries to keep playing his keytar, but he has a spare set in his car trunk. Unfortunately, the batteries are in one of his dozens of keytars, and he does not remember which one. Meanwhile, Marco's state of being stuck in the drainage pipe attracts the unwanted attention of the Echo Creek fire department.
After Miss Skullnick retrieves Marisol, she heads back to check on the kids in detention. As Star listens to Oskar's music, Janna mentions that they have four minutes to return to the detention room. They quickly check each keytar in Oskar's car before finally finding the spare batteries. On the race back to detention, Star conjures a giant six-legged porcupine to go faster. As Star and Janna approach the detention room, they notice Miss Skullnick ahead of them and just inches away from the room door. Luckily, Miss Skullnick is scared off by the snake in the can of potato chips, allowing Star and Janna to return to the room before Miss Skullnick realizes that they were gone.
Using the batteries that Oskar provided, Toby turns on the television across the hall just in time for the kids to watch wrestling. Janna relieves Star of her duties as "Mayor of Detention" and says she can leave if she wants, but Star decides to stay and watch the wrestling match. She even appoints Janna as her "Deputy Mayor".
- Eden Sher as Star Butterfly
- Abby Elliott as Janna Ordonia
- Adam McArthur as Marco Diaz
- Dee Dee Rescher as Miss Skullnick
- Jon Heder as Oskar Greason
- Grey DeLisle as Jackie-Lynn Thomas
- The episode's title is a play on "girls' night out".
- Miss Skullnick's first name is revealed to be Margaret in this episode.
Promotional and Concept