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PJ Masks Wiki

"Big Sister Motsuki"
Season 3, episode 25A
(Overall episode #148)
Premiere date
United States of America United States of America
February 7, 2020
Written by Simon Nicholson
Directed by Christian De Vita
Viewer count (millions) TBA
Episode Guide
"Gekko Takes Charge"
"PJ Party Crasher"

"Big Sister Motsuki" (also known as "Motsuki grande soeur" in French) is the first segment of the 25th Season 3 episode of PJ Masks.


Motsuki steals Romeo's Baby Beam and turns him, Luna Girl and (with the help of Baby Luna) the PJ Masks into bad-behaved babies.


The following characters appeared in the episode "Big Sister Motsuki":


The episode begins as Motsuki spies on Romeo and Robot attempting to rebuild all the inventions that the PJ Masks either destroyed or put in their headquarters. When she hears that they made a portable version of the Baby Beam, she gets an idea and takes it from them. She approaches Luna Girl, who is demanding her to steal things, and zaps her with the invention, intending to make her her little sister so she can do whatever she says.

The next day, all the art supplies are scattered around the school, and some of the art projects are splattered with paint. That night, the PJ Masks see in the PJ Picture Player that Motsuki stole the Baby Beam and turned Luna Girl into Baby Luna. Seeing that she’s painting on more objects besides the canvas, the team heads off to stop her.

In the forest, Motsuki is taking pleasure at telling Luna Girl what to do, although she gets angry at her for throwing a paintbrush at her. The PJ Masks arrive and confront Motsuki, but she traps them into bubbles, and they float away. At the same time, Romeo and Robot arrive at the scene and demand Motsuki to hand back the Baby Beam. The three spot the invention and Robot tries to grab it, but Motsuki zaps him as well, and he is bubbled. He floats away, dropping the Baby Beam, and the impact causes the invention to activate and zap Romeo into a baby as well.

Motsuki proceeds to tell the baby villains what to do. Meanwhile, the PJ Masks float back to headquarters. PJ Robot frees them by zapping the bubble shields and shows them through the tablet that Romeo has also been zapped. Catboy, Owlette, and Gekko follow the villains to the school as they leave more mess behind. They try to confront Motsuki again, but Luna Girl zaps them with the Baby Beam, and they are turned into babies. With everyone now turned into a baby, Motsuki leads them inside the school.

Inside the classroom, the baby heroes and villains are running around and throwing things everywhere. Motsuki grabs their attention with a loud squeak and tells them to listen to her. She tells the group to be bad, and they proceed to do just that. Motsuki, though, is pulled along with their antics. As she is carried outside, the group throws her around, using their powers on her. She demands them to do what she says, but the group continues doing what they are doing.

PJ Robot suddenly arrives in the PJ Seeker and sees all the commotion. Motsuki asks him to help, and he grabs a volleyball for the kids to play with. They drop Motsuki, and they proceed to play catch. Motsuki asks him how did he get the kids to listen, to which he responds that he was nice to them. Motsuki counters this by saying that she is mean, and that it only works for the PJ Masks since they are nice already, but when she sees the team pass the ball to Romeo and Luna Girl, she is taken aback and, although reluctantly, decides to witness how PJ Robot treats the five baby-turned kids.

Everyone returns back to the classroom, and PJ Robot teaches them how to be nice. He gives the PJ Masks art supplies so they can draw, gives Romeo and Luna Girl a drink as they play with the building blocks, and assists the group with whatever they need help with. While the montage is happening, Motsuki slowly realizes that each behavior that a big sibling exhibits will cause the younger siblings to act as she does. Therefore, if she acts nice, then the group will act nice as well. She then follows what PJ Robot did before, and she ends up enjoying the kids’ nice behavior. The babies give her a group hug, and Motsuki tells them that she loves them.

PJ Robot suddenly notices the Baby Beam on the desk. He re-adjusts the setting, but Motsuki zaps him into a bubble shield before he could zap the five babies back to normal, not wanting to become a little sister and have the kids become big again. She grabs the invention as it drops to the floor, but she notices the kids’ reaction. She figures out that the kids won’t be able to grow up, just as she won’t be able to do so herself. With this in mind, she decides to zap the group into big kids again and zap PJ Robot free.

The group is back to normal, unaware of what happened, but when PJ Robot tells the PJ Masks they were bad babies turned good thanks to him and Motsuki, they remember that they were stopping babies Romeo and Luna Girl because they thought they were trouble. Despite that, PJ Robot liked them and knew they could be nice, and the team hopes that they could be that way from now on. However, Romeo and Luna Girl quarrel with each other, and after being meanly treated, Motsuki chases them out of the classroom. Nevertheless, thanks to PJ Robot, there are no more baby villains to fight, and the team shouts out their signature victory phrase.


  • Teach others how to be nice instead of teaching them how to be bad.


  • This episode, along with "PJ Sky Pirates," is one of the post-"The Prank Wheelz" episodes to have Romeo's Lab.
  • Romeo's Baby Beam makes a returning appearance in this episode. This time, it is designed as a handheld gun.
    • It was first introduced in "Terrible Two-Some."
    • This marks the second time Catboy and Owlette get zapped by the invention, the first time being in the aforementioned episode.
    • This also marks the first time Luna Girl, Romeo, and Gekko get zapped by the invention.
    • Also in some scenes, Luna Girl (as a baby) can be heard imitating Motsuki's moth squeaks.
  • Kitten Boy and Chicklette return in this episode.
  • Romeo and Robot meet Motsuki for the first time.
  • This is the second time Motsuki narrates a title of an episode.
  • Motsuki is the third villain Luna Girl used her magnet's power on.
  • Luna Girl gets zapped by one of Romeo's inventions for the first time.
  • This is the fourth time Catboy and Owlette get taken over by Romeo's inventions.
  • In the classroom, we see Romeo’s terrible drawing of him getting superpowers, which is from "Wolfy Powers."
  • The PJ Masks' victory quote was given slight alterations to "PJ Masks, all shout hooray! 'Cause in the night, PJ Robot saved the day!"
  • Starting with this episode, Luna's eye color is now more of a purplish-blue than regular blue.
  • Luna Girl (as Baby Luna) uses one of Romeo's inventions for the second time.
  • PJ Robot is called "PJ Bot-Bot" for the first time.
    • Robot was also called simply "Bot-Bot" for the first time.
  • PJ Robot is shown to love babies.
  • Motsuki is seen inside the school for the first time.
Episode list
| Blame it on the Train, Owlette | Catboy's Cloudy Crisis | Owlette and the Flash Flip Trip | Catboy and the Pogo Dozer | Gekko and the Super Ninjalinos | Owlette's Terrible Pterodactyl Trouble | Catboy and the Shrinker | Owlette and the Moon-Ball | Catboy and the Butterfly Brigade | Owlette the Winner | Speak UP, Gekko! | Catboy and Master Fang's Sword | Catboy VS. Robo-Cat | Owlette and the Giving Owl | Catboy and the Great Birthday Cake Rescue | Gekko and the Snore-A-Saurus | Looking After Gekko | Catboy and the Teeny Weeny Ninjalino | Catboy's Tricky Ticket | Gekko and the Missing Gekko-Mobile | Catboy's Flying Fiasco | Gekko's Stay-at-Home Sneezes | Gekko Saves Christmas | Gekko's Nice Ice Plan | Gekko and the Mighty Moon Problem | Clumsy Catboy | Catboy and Gekko's Robot Rampage | Owlette's Feathered Friend | Owlette and the Battling Headquarters | Gekko and the Mayhem at the Museum | Catboy Takes Control | Owlette's Two Wrongs | Gekko Floats | Catboy's Two-Wheeled Wonder | Catboy's Great Gig | Owlette's New Move | Supersonic Owlette | Catboy and the Sticky Splat Slingshot | Owlette of a Kind | Beat the Drum, Catboy | Catboy Squared | Gekko's Super Gekko Sense | Owlette and the Owletteenies | Gekko's Blame Campaign | Owlette and the Moonflower | Slowpoke Gekko | Catboy and the Lunar Dome | Gekko and the Rock of All Power | Super-Sized Gekko | Take to the Skies, Owlette | Slow Down, Catboy! | Gekko's Special Rock |
| Moonfizzle Balls | Soccer Ninjalinos | Lionel-Saurus | Catboy's Cuddly | Night of the Cat | Catboy Does It Again | Terrible Two-Some | Owlette's Luna Trouble | Ninja Moths | Who's Got the Owl Power? | PJ Pinball | Bounce-a-Tron | Wacky Floats | Romeo's Disguise | PJ Robot | PJ Power Up | Moonstruck: Race to the Moon | Moonstruck: Lunar Fortress | Robot's Pet Cat | Gekko, Master of the Deep | May the Best Power Win | Moonbreaker | Race Up Mystery Mountain | The Mountain Prisoner | The Wolfy Kids | Wolf-O-Saurus | Catboy No More | Gekko Vs. the Splatcano | Meet Armadylan | Invisible Owlette | Wolfy Mountain | Romeo's Crystal Clear Plan | Nobody's Sidekick | Armadylan Menace | Power Pondweed | Owlette Comes Clean | Halloween Tricksters | The Wolfies Take HQ | The Good Wolfy | The Wolfy Plan | The Lizard Theft | PJ Dylan | Armadylan'd and Dangerous | Romeo's Action Toys | The Dragon Gong | Flight of the Ninja | Romeocoaster | Gekko and the Opposite Ray | PJ Masks Vs. Bad Guys United | Easter Wolfies | Luna and the Wolfies |
| Moon Madness | Armadylan and Robette Rule | Armadylan Zen | Way of the Woofy | Werejalinos | PJ Comet | Glowy Moths | Teacher Goes Ninja | Robot Goes Wrong | Lionel's Powers | Best Friends Forever | Meet An Yu | The Moon Prix | Pirates Ahoy! | The Secret of the Pagoda | Storm of the Ninja | Arma-Leader | Owlette Slips Up | The Splat Monster | Moth on the Moon | Fly Me To The Moon | Luna's Cosmic Tantrum | Motsuki The Best | Wheels of a Hero | Moonwolfy | Clash on Mystery Mountain | A Teeny Weeny Problem | Take Romeo Off The Road | Mission: PJ Seeker | Wolfy Powers | Do The Gekko | Armadylan, Action Hero | Super Muscles Show Off | The Prank Wheelz | Where's The Wolf Wheelz? | Villain of the Sky | Protector of the Sky | The PJ Masks Save Christmas | Romeo's Melody | PJ Robot Takes Control | PJ Sky Pirates | The Disappearing Ninjas | Gekko Everywhere | Gekko Takes Charge | Big Sister Motsuki | PJ Party Crasher | Master of the Moat | PJ Robot Vs Romeo |
| Heroes of the Sky | Who Let the Moths In? | Commander Meow | Motsuki's Missing Sister | Not so Ninja | PJ Party Mountain | Wolfies of the Pagoda | Master Fang's Secret | Aerodylan | Asteroid Accident | All About Asteroids | Romeo's Space Machine | Newton and the Ninjas | Missing Space Rock | Flying Factory Out of Control | Munki-gu | Munki-gu in the City | Mission Munki-gu | Legend of the Wolfy Bone | Gekko Vs Armavillain | Super Super Cat Speed | Munki-gu's Dragon | Gekko Loves Lionel | Octobella | Octo-Trouble | Star Buddies | To the Moon and Back | Magnet in the Moat | Motsuki Bugs Out | Octobella's Garden | Sploshy Splash | Teeny Weeny Returns | Robo-Wolf | The Labours of Armadylan | Lost in Space | The Power of Monkey Chatter | The Secret of Monkey Goodness | Pharaoh Boy | By My Pharaoh Feathers | Pharaoh's Chariot | PJ Robot Malfunction | The Mysterious Masks | Battle Of The Fangs | Catboy's Cat | Mad With Moon Power | Pharaoh and The Ninjalinos | Pharaoh's Boomerangs | Bubbles Of Badness |
| Ninja Power Up | Luna Goes Too Far | Owly Tricks | Newton The Destructor | Luna Kazoomer | Baddie Bots | Newton and the Animals | Octobella Strikes Again | Octobella on the Loose | Teeny Weeny to the Rescue | Invisible Munki-Gu | Orticia Blooms | Orticia and the Pumpkins | Pirate Robot | Owlette, the Pirate Queen | Catboy's Magic Trick | Gekko The Croc | The Camping Trip | Pondweed Party | A Percival Problem | Luna Girl's Sleepover | Dragon Dance | An Yu and the Cave Stones | Midnight Snack Attack | The Voyage of the Golden Asteroid | Carly and Cartoka | The PJ Riders | Flashcar in the Sky | Luna's Mega Moth | Captain Pirate Robot | Crash Track Trick | Gekko's Speedy Lizard | Night Ninja's School of Ninja Naughtiness | The Jolly Ninjalino |
To be announced.
| Super Cat Speed | Super Gekko Muscles | Owl Eyes | Reinvention | Moth's Day | Super Moves Dance Party | Super Gekko Camouflage | Teamwork | All Skills | Determination | Gekko Improvises | Super Singing Heroes | Team Night Ninja | Super Cat Ears | Owlette Improvises | A Job For All | Bravery | Catboy Improvises | Taking Turns | Training with the PJ Masks | Moon Rocked | Play Date on the Moon | Space Race | Cat-Car Chaos | Gekko-Mobile Mischief | Robots Wash Up | Owl-Glider Gliding | Armadylan Style | Wolfy Garden | Bye Bye Bad Luna | Catboy Power Up | Owlette Power Up | Gekko Power Up | Masters of the Mountain | Moon Cuddly | The PJ Rovers | PJ Racing | An Yu's Bird Rescue | PJ Masks Surprise | Ninjability | HQ Tour | Minding Motsuki | It's A PJ Masks Christmas | Learning the Planets |