Maturing Bubbles

"Maturing Bubbles" is the seventh episode of the seventh season of The Powerpuff Girls, as well as the revival, and is the 143rd episode of the entire series overall. The episode of scheduled for April 15, 2019 on Max.

Plot
The Professor introduces his latest invention to the Girls: the Aging Ray. Testing it out on an apple, the Girls are amazed by what it does. Curious, Buttercup wants to try it out on something else, but to her dismay, the Professor says that after a single shot, it must recharge for 24 hours. On the following day, the Professor heads out, giving Buttercup time to go into the lab and use the Aging Ray. Unfortunately, Blossom catches her with it and they fight over it. Blossom pulls it out of her hands and accidentally pulls the trigger, ricocheting the blast around the lab. As Bubbles comes in, the blast hits her, aging her up to 16. Worried, Blossom and Buttercup approach their sister, who simply has no memory of what happened as the effects of the ray have also effected her mind as well. As Blossom worries about the outcome, Buttercup sees the upside as she thinks teenagers "are able to do stuff as adults do", in which Blossom dismisses.

Sneaking her into their room, they decide on whether or not tell the Professor about Bubbles, but when he returns home the teenage Bubbles shouts, "Hi, Daddy!" and flies down to greet him (as well as saying that she hasn't seen him in five years). After Blossom and Buttercup explain what had happened, the Professor, so he will have to make a reverse-Aging Ray to change her back as the ray he has now it only ages things forward, which could take a few days, much to Blossom's disappointment and Buttercup's elation. The hotline rings and the Mayor informs them that a giant octopus is attacking the city. they head downtown and they find the octopus (who appears to be the same one from "Octi Gone") about to destroy a sushi shop. When Blossom and Buttercup try to drag it away, Bubbles tosses the octopus into the sun.

A day later, the Girls arrive at Pokey Oaks, where Bubbles flies over to hug Ms. Keane, referring to her as "Mom", much to Blossom and Buttercup's surprise and to the students and Keane's confusion. After Blossom explained, the Girls take their seats. Later that night, Bubbles takes up the whole bed and has Blossom and Buttercup sleep on the floor, as of "being the older sister". Throughout the next day, they suddenly get disgusted with the teenage Bubbles, as does the Professor. Fortunately, the Professor had finished the Reverse-Aging Ray last night, so they can change her back. When Bubbles returns with some pizza, they inform them that the ray is finished and they can return to normal, After Bubbles asks for some time to think about it, she flew away in secrecy, leading to Blossom and Buttercup to follow her. Having lost her, they concoct a plan to lure her to them. Later, Bubbles finds a chihuahua in the middle of the road that is about to get run over by a large semi truck, in which she rescues. She gets frozen in place by Blossom's breath, in which the chihuahua rescue turned out to be a trap.

Returning back to the lab, the Girls hold Bubbles as the Professor blasts her with the ray, reverting her back to normal. Unfortunately, it suddenly aged down Blossom and Buttercup into infants, much to Bubbles' excitement and the Professor's shock; making him faint. The episode ends with the narrator saying, "So once again, the day is saved! No thanks to Bubbles.", referring to the teenage Bubbles, who takes offense to it.