SMG4: Mario and the Experiment is the nineteenth episode of Season 9 and the four hundred and ninety-ninth overall to be uploaded by SMG4.
This is the tenth episode and third episode of the 2nd part of The Anime Arc. It was aired on May 25, 2019.
Mario and friends are off to save Meggy. But what has happened to her?
The episode continues with where The Inkling Disappearances left off. Axol greets Meggy while the latter is surprised to find out that Axol wasn't actually the one who kidnapped her and summoned all those anime characters, and rather was held captive as well. Suddenly, the two hear a menacing laugh of the true culprit, who turns out to be none other than Francis. He says that Axol doesn't have enough courage to do what he has done, and calls Axol a "disappointment". Meggy begins to rant on Francis about why would he ever do such a thing if Axol even lifted the anime ban for him. Francis then mentions the show that Axol and his team have presented to Peach in order to unban anime and comments that how they did it was rather pathetic (he was likely expecting violence). He summons Mewtwo and says that he's going use Inkweaver the way it's "supposed to".
Seeing his magic pen being used for malicious purposes, Axol tries to tell Francis not to do that, only to be force choked by Mewtwo. Meggy then gets very scared for Axol's life and begs Francis and Mewtwo to stop it. As Mewtwo stops choking Axol, Francis begins to laugh insanely and then takes Meggy to the room where the Inkling ink is extracted and stored. He then confirms he and the Anime Cartel have captured half of the whole Inkopolis population and says Inkweaver has 70% power.
Meggy then asks him why would he kidnap hundreds of thousands of innocent Inklings just for some "stupid" cartoons, to which Francis responds that his plans are far beyond that, and presents "The Ink Zuccer 2000". He starts bragging about his invention's strength and then says that he'll harvest the ink of a "Very Special Inkling" so he can power the Inkweaver up to 100% to have his very own "island full of waifus", before getting kicked in the face by Meggy. He then calls Mewtwo for help, and, as Mewtwo drags Meggy into the "Ink Zuccer", he continues hoping that Meggy is tough enough to completely max out the Inkweaver's power. Meggy begins pleading for help from Mario and his crew.
As it turns out, Mario and his friends are still heading towards Anime Island. Mario keeps repeatedly asking if they are there yet, Luigi takes a nap, SMG4 is seen using his computer and then complaining about something and saying "Goddamn it!", while Swagmaster plays pirates together with Fishy Boopkins and Bob, much to Chris' annoyance. Meanwhile, Tari and Saiko are seen standing together on the front of the ship. Tari is afraid that they may never find Meggy, but Saiko then cheers her up and promises that everything will be fine. Shortly after that, Mario continues repeatedly asking if they are there yet until severely irritated SMG4 loses his patience and then runs up to him, telling him to shut his mouth for once.
Suddenly, their trip is once again interrupted by Godzilla, who makes a reappearance following his abduction of Desti. The crew tries to take him down once again, with Saiko and Swag attacking him with their hammers, and multiple ship cannons shooting at him, but, unfortunately, none of their efforts prove successful. The monster then proceeds to slam his hand against the ship, making SMG4 take a flight. Seeing that, Bob immediately throws a waifu pillow towards SMG4, softening his landing, and then cheers about anime girls ("2D boobies" if exactly) "saving the world once again".
Seeing all their efforts were rendered futile, Tari complains that they need something stronger, to which Luigi responds complaining that they do not have anything stronger at all, utterly panicking. Godzilla slams his hand against their ship once again, nearly crushing Tari. Fishy Boopkins saves Tari from Godzilla but then gets blown away by the kaiju's giant hand himself, proceeding to summon Fishy Boopkins' Dad.
Meanwhile, on the Anime Island, Meggy is just about to be thrown into the Ink Zuccer by Mewtwo who is told to hurry up by Francis, before Desti is taken to the room by Pikachu and Hatsune Miku, criticizing the interior design and Francis' hygiene. Meggy gets quite shocked about discovering that Desti has also been captured, while Francis gets excited about getting an Octoling and tells his anime servants to bring her up along with Meggy. However, Desti reveals that she's here to save Meggy and then kicks Francis in his face. Mewtwo then releases Meggy without throwing her into the Ink Zuccer and quickly turns to Desti, firing towards her. However, Desti tricks him, as his projectiles only end up breaking her handcuffs, and then she proceeds to rescue Meggy.
As the girls run away from Francis' anime minions, Desti asks Meggy where is the exit, to which Meggy answers that she has no idea, much to Desti's surprise. Desti then asks her why she doesn't know the way out, Meggy starts to complain about how she is supposed to know if she was a prisoner, not a tourist. Eventually, the two are suddenly spotted by Miku and Pikachu who start firing towards the girls, and Desti tells Meggy to quickly hide in a room nearby - just to realize that they are trapped in there.
Desti then proceeds to octoform, and suggests Meggy to squidform along with her, but Meggy recalls the fact that her hands are still cuffed up, and answers that she cannot turn into a squid because of her handcuffs. Suddenly, shortly after Desti transforms back into her humanoid form, the girls hear Pikachu and Miku unlocking the door, and proceed to hide from them in the locker. As Pikachu and Miku explore the room trying to find the girls, Pikachu manages to approach the locker in which the girls are hiding from them and takes a peek into the locker's keyhole, much to the girls' shock, but, thankfully, doesn't notice them and leaves the room together with Miku.
The girls then hop out of the locker. Desti decides to remove Meggy's handcuffs with her barrette. Meggy thanks Desti for helping her out, but then also asks her why is she helping her if she's supposed to hate her. Desti answers that, frankly, she still doesn't actually like her very much, but wants her humiliated rather than dead - and adds that saving her life is probably the most humiliating thing Desti can ever do to Meggy. Meggy then reminds her that someday, she will return the favor to herself, but Desti expresses her doubts about that and tells her to go.
Eventually, the two leave the room where they were hiding. Desti then reveals that Meggy's friends are finally sailing to the Anime Island, adding that they probably would have come sooner if Mario didn't have to load the whole boat with food first. The two get cheered up quite a bit before suddenly hearing Axol's voice. They discover that they are actually right below Axol's cell, who is being beaten by two Anime Cartel members - a Goomba and a Boo. He tries to explain to them that Francis is actually using them and would never share his waifus with them, but they do not listen. They continue to spank Axol and laugh hysterically before Meggy and Desti hop out from the vents and proceed to beat them up.
Axol thanks the girls for taking advantage of him distracting the Anime Cartel minions while Meggy quickly finds a key and proceeds to free him. Desti apologizes to Axol for accusing him of abducting Meggy and all the other Inklings. Axol accepts the apologies and sincerely says that he would never do such a thing since Meggy and all of the SMG4's crew are all his friends. Suddenly, an alert alarm rings and dozens of other Anime Cartel minions start to storm the cell. Axol then admits that without his trusty Inkweaver he would be no match against them, and suggests the girls to do the job instead. The girls then agree and begin betting on who's going to knock more Anime Cartel minions out.
Meanwhile, in the sea, a fight is onset between Mr. Boopkins and Godzilla. Fishy Boopkins points at Godzilla and tells his dad that Godzilla is the one who abused him and his friends. However, Godzilla proves to be a much more difficult opponent than what Mr. Boopkins usually faces. After a brief moment of fighting, Godzilla notices a plane which is flown by Mugman. He proceeds to catch the plane and then launch it towards Mr. Boopkins, knocking him out, and then points a gun at him. The crew then decides to shoot the monster with the boat's cannons, only for him to complain about how weak those efforts to stop him are. Fortunately, Mario distracts Godzilla at a crucial moment by accidentally launching himself out of a cannon and then getting right into kaiju's eye. This allows Mr. Boopkins to defeat Godzilla.
After the hard battle, Mr. Boopkins puts his son back on the boat. Fishy Boopkins then thanks his dad for saving his friends, and promises that he will visit him once Meggy, Desti and Axol are saved. Mr. Boopkins asks his son if he had finished his homework, to which Fishy Boopkins answers positively and then gets a yummy ice cream as a reward before his dad says goodbye to him and his friends and leaves. Meanwhile, the Mario brothers and Saiko finally spot the Anime Island on the horizon.
On the Anime Island, Meggy and Desti show all their best in taking down the Anime Cartel minions and confirm to have knocked eight of them out each before noticing only one Goomba left, who begs for mercy. However, the girls are swiftly knocked out by Super Saiyan Goku, who launches a Kamehameha at them. Not only Axol got very shocked for the girls, but also for the fact that Francis has already powered the Inkweaver up to 70% to summon Super Saiyan Goku. Francis then begins to brag about the power he could achieve with Meggy's and Desti's ink - which, by his estimations, would be enough to summon a "Super Saiyan God". Axol denies that and attempts to beat up Goku, but gets knocked out by him in one punch.
Shortly after that, Axol is put in a straitjacket and is chained along with Desti. Francis decides to have the two of them watch while he extracts Meggy's ink. Goku is seen holding Meggy over the Ink Zuccer 2000. As Desti begs Francis to "let her go", Goku literally "lets her go" by dropping her right into the Ink Zuccer. The episode ends on a cliffhanger with Meggy falling into the Ink Zuccer which then closes, making it uncertain whether there is anything possible to save her or not.