The episode opens with the PJ Masks, their classmates and their teacher taking a walk in the park. Greg spots some of Luna Girl's moths, hanging up posters of a missing moth. Amaya actually feels sorry for Luna since the moths are her only companions. Connor reminds her she also constantly fights with them, but nevertheless agrees to investigate. So that night the three friends transform and meet up in HQ.
Using the PJ Picture Player, they spot Luna Girl, clearly depressed. When they go to her, she tearfully confesses that the moths ditched her since they considered her too bad. Owlette offers to help Luna Girl make new friends, and Luna Girl states she will stop being bad. Owlette even agrees to let Luna come with them to HQ. Catboy doesn’t like the idea, so Owlette promises to keep an eye on Luna. While the PJ Masks discuss the situation, Luna Girl sneaks off to the elevators, and goes up to the door, where Mothzuki is waiting for her. We learn now the whole thing about the moths leaving her was just an act so she can trick the PJ Masks into taking her to the moon.
The PJ Masks still don’t suspect a thing, nor do they notice Luna smuggled Mothzuki into HQ. Owlette invites Luna to her room, where she tells Luna about her various powers. Mothzuki fears that Luna actually begins to like Owlette as a friend. To prove her wrong, Luna tells Owlette she heard Romeo is working on a new invention that will allow him to tunnel into HQ. When the PJ Masks go outside to investigate, Luna Girl and Mothzuki lock them out of HQ. Luna then prepares to take off with HQ to the moon, but when she opens the door of Owlette’s section to let her moths in, Owlette also sneaks back into HQ.
Owlette can’t prevent Luna from activating the rocket mode however, and HQ takes off into the sky with Gekko and Catboy clinging onto its side. Owlette leaves HQ to help her friends first. She helps them both to get back into HQ just before it reaches space and transforms into rocketship mode. The 3 PJ Masks quickly take their seats and put on their seatbelts, but Luna Girl ignores Owlette’s warning to do the same and the turbulence from going into orbit causes her to fall into the elevator, and out of HQ.
Unable to stand by and do nothing, Owlette decides to help Luna. Then Catboy notices an asteroid storm coming their way. Owlette has already left the rocket however. She gets to Luna, but then the asteroids reach them. Catboy and Gekko also leave the rocket and manage to save the girls, but now they are all floating in space, while more asteroids are heading for the rocket. Catboy urges Luna Girl to use her magnet to get them back to the rocket, but Luna Girl already used up almost all the magnet’s powers for her plan.
The asteroids hit the rocket and damage the engines. The PJ Masks offer Luna Girl to get herself to the rocket and leave them, stating they’re heroes and will figure something out. This prompts Luna Girl to be a hero herself for once and save the PJ Masks, despite the risks. She uses her magnet to pull them all towards the rocket. They barely make it before the magnet completely runs out of power.
Once the engines are repaired, HQ returns to the city. The PJ Masks tell Luna she could be an actual friend if she wanted to, but she declines. Then Owlette walks up to Luna Girl and hugs her thanks, getting her disgusted and calling the PJ Masks 'so mushy' and adds that she could never have them as best friends, but Luna and her moths and Mothzuki join them in the PJ Masks’ victory pose anyway at the end.
This is the third time Luna Girl gets invited into HQ.