Short Version (TL;DR): In “Moon Girl’s Day Off,” Lunella fakes a twisted ankle to get some rest from her busy life. Casey takes her place as Moon Girl but struggles with the responsibilities. When a reluctant villain named Abyss returns, Lunella realizes the importance of honesty and gets help from her grandmother. They defeat the villain together, and Casey forgives Lunella, now that she understands how busy Lunella is. Meanwhile, Abyss decides to switch careers and give up being a villain.
The Struggles of a Hero
The stress of balancing the life of a superhero with school and socializing is starting to take a toll on Lunella’s health. Despite her exhaustion, she manages to defeat Abyss, a reluctant fifth-generation supervillain. When Casey schedules an all-day photoshoot, Lunella lies about twisting her ankle so she can rest. She gives Casey a modified version of her Moon Girl suit to go in her place.
Casey and Devil attend the photoshoot, which goes smoothly. Over time, Casey finds herself struggling with the unwanted attention and hard work that comes with being Moon Girl. To make matters worse, Abyss returns to seek revenge. Although she wants to help, Casey isn’t prepared to take on a villain alone. Aware of Lunella’s deception, Devil calls her to tell her about the situation. He then tries to protect Casey by hiding her while he confronts Abyss by himself.
Heart-to-Heart with Mimi
Meanwhile, Lunella frequently asks things of Mimi, who suspects that Lunella is faking her injury. They have a heart-to-heart discussion about the importance of honesty with the people who love you. How can they offer proper support if you never communicate your needs to them?
Lunella receives Devil’s call while talking with Mimi, and she asks her grandmother for a ride to help Casey with a “project.” They hop on Mimi’s motor scooter and speed into Little Italy.
A Karmic Twist
While trying to help Casey, Lunella’s skates get caught in a grate, causing her to twist her ankle for real. Despite her now genuine injury, Lunella and Casey manage to freeze Abyss in a block of ice. Lunella admits that she lied, but Casey quickly forgives her. Casey finally comprehends the challenges Lunella faces and agrees to let her rest. Abyss escapes, but she’s been inspired by Lunella and Casey’s friendship. She calls her mother to announce that she’s done being a villain and is switching careers.
Be sure to catch new episodes of Moon Girl and Devil Dinosaur on Saturdays at 8 PM EDT on the Disney Channel, or stream them anytime on Disney+.