Lilo tries to use a duplicating experiment to clone herself but Stitch and Pleakley get cloned instead. Then Gantu gets his hands on this experiment and decides to duplicate four other experiments he recently activated after capturing them in pod form.
Lilo and Stitch capture an experiment and brings it to Jumba for identification. He says that the experiment is 344, a duplicator that can make copies of objects or people, but less powerful than the original. Pleakley is worried that the experiment will cause problems at Lilo's slumber party that night, so Jumba says he will keep it in his ship. The only problem is that none of Lilo's friends actually show up for the sleepover, only some of Stitch's cousins.
Gantu storms into his ship, furious at yet another defeat at the hands of Lilo and Stitch. Reuben calms him down and gets him to think about the underlying cause of his rage, which eventually leads Gantu to talk about his friend-less, lonely childhood. Reuben acts therapeutic at first but eventually gets fed up with Gantu's whining and tells him to can it. Gantu stomps off and roams the streets of Kokaua Town, muttering to himself about how his failures are all the fault of Stitch. He sees four experiment pods for sale in a pawn shop and steals them, planning to build an army to defeat Stitch once and for all. Gantu activates the four experiments and begins to train them into a threatening combat unit designed to kill Stitch. He even uses Reuben as target practice for the new experiments, who gets pretty seriously beaten up.
The slumber party is going well for Stitch, but Lilo is sad that she can't ever seem to make friends. She wishes that she could make a whole bunch of friends, but realizes that she has just the way to do that. She sneaks onto Jumba's ship and tries to use 344 to clone herself into friends "just like her." However, Stitch notices what she was doing and leaps in at the last moment, causing him to get duplicated instead. Pleakley sends all of Stitch's cousins home as Stitch's three clones begin to wreak havoc across the house. Jumba brainstorms a way to reverse the duplication process, but Lilo is reluctant because the Stitch clones can be her posse. The real Stitch lays down on the couch, looking very tired and weakened. It seems the cloning process has taken a toll on him...
Lilo goes to hula class with her new three clone friends, bragging to Mertle about her new posse and how she's having another slumber party without her. Meanwhile, Gantu has trained up his new task force and sends them out to hunt down Stitch. Unfortunately, the Stitches are only a quarter as powerful as usual because he was split into four copies. Gantu easily captures all four clones with the help of his new army. They return home for a victory feast (which Reuben prepares under the threat of more beatings) and plan to capture all the experiments the same way.
Lilo and Jumba make a plan to sneak onto Gantu's ship, cloning Pleakley to act as a distraction. The Pleakleys pose as deliverymen and Lilo and 344 sneak to where the Stitches are being held. However, Gantu immediately recognizes Pleakley and sees through the ruse, grabbing 344 as an addition to his army. Lilo tricks him into making 100 copies of each experiment in his army, and this makes them so weak that Pleakley takes them all on single-handedly. Lilo uses 344 to reverse the cloning process on Stitch and make him whole again, leaving Gantu with a massive, worthless army. At least Reuben is willing to forgive him.
Back at home, Lilo realizes that it's not the number of friends she has that matters because she already has amazing friends. 344 (now named "Dupe") finds his one true place at a shave ice standnote using his duplication abilities to clone shave ice into half-calorie versions of the original.
Experiments who appeared or were mentioned in this episode:
- Hammerface (X-033): One of Gantu's experiments used as his personal army. During the fight in the Pelekai residence, the grey hammer-headed experiment hammered the end of a floorboard to knock a Stitch clone into a containment capsule held by Gantu.
- Dupe (X-344): This episode's Monster of the Week; a golden-yellow, monkey and lemur-like experiment who can make copies of anyone or anything, with the minor side effect of copied objects being less powerful than the original.
- Yin (X-501): One of Stitch's guests at the slumber party. She wears a pink nightgown and nightcap.
- Yang (X-502): One of Stitch's guests at the slumber party. He wears green boxers and bunny slippers and brings his own pillow to sleep with.
- Richter (X-513): One of Stitch's guests at the slumber party. He wears a yellow onesie and brings a teddy bear to sleep with.
- Cannonball (X-520): One of Stitch's guests at the slumber party. He wears light blue pajamas with white clouds on them.
- Thresher (X-544): One of Gantu's experiments used as his personal army. During the fight in the Pelekai residence, the purple slug-like experiment with six stretchable mace-like tentacles appeared to be mesmerized by a Stitch clone spinning a broom like a bo staff, but he actually distracts the clone by tapping his shoulder with a tentacle wrapped around from behind before knocking him out with another.
- Heat (X-609): One of Gantu's experiments used as his personal army. During the fight in the Pelekai residence, the red-orange dog/koala-like experiment fires a laser from the big, black, bulb-like heating element on his forehead to create a hole in the Pelekais' couch as a Stitch clone struggled to hold it above his head, causing it to collapse on top of the clone and knock him out.
- Plasmoid (X-617): One of Gantu's experiments used as his personal army. During the fight in the Pelekai residence, the green scorpion-like experiment fired red plasma balls from his tail at the last Stitch clone remaining, knocking him out by firing at an overhead lamp that falls on the clone after a few seconds swinging above it.
- Reuben (X-625): Boy, does he take a lot of punishment from Gantu's new squad.
Notably, the four experiments in Gantu's squad are some of the only known experiments to be named by someone other than Lilo.
Tropes featured in this episode include:
- Bad "Bad Acting": Lilo is both overly-dramatic and flat when acting upset about Gantu into making multiple clones of his squad, including a melodramatic Big "NO!". It's so obvious, Gantu honestly deserves a pay cut just for not seeing through it.
- Borrowed Catchphrase: The Stitch clones borrow the drawn out "Yeah!" from Mertle's Girl Posse.
- Briar Patching: After Gantu notices Lilo and Dupe, grabbing the latter, Lilo tricks Gantu into cloning his experiment army to 100 of each, not knowing that doing so will reduce them to only 1% of their original strength.(Lilo notices Gantu's experiments surrounding the three Pleakleys and gets an idea.)
Lilo: (points at Gantu) Don't you dare touch him! He doesn't want to make copies of all your evil experiments!
Gantu: Making copies of my army... That's an inspired idea! I'll make a hundred of each of them! Not even Hämsterviel will be powerful enough to stop me! - Bring It: The restored Stitch does this to Gantu, ultimately throwing him through a wall.
- Butt-Monkey: Reuben, as Gantu's new personal army repeatedly uses him as a living punching bag during their training. Gantu also demotes him to a butler and forces him to wait on his new army hand and foot. While Gantu has never exactly treated Reuben well, this goes above and beyond the usual.
- Cloning Gambit: Lilo and Jumba clone Pleakley in order to act as a distraction.
- Cloning Splits Attributes: Side effect of Dupe's cloning, rendering him a failed experiment. This is both what gets the Stitch clones kidnapped and what leads to the downfall of Gantu's army. Clearly, he’s best used on inanimate objects.
- Delivery Guy Infiltration: Jumba has Dupe make three Pleakleys, who do this to get inside Gantu's ship. It takes Gantu a moment to catch on.
- Exactly What I Aimed At: At the end of the fight, Plasmoid tries to fire several plasma balls at a Stitch clone, but the clone dodges them. He then aims his last ball at an overhead lamp above the clone. It swings for a few seconds, causing the clone to mock the experiment for missing, only for the lamp to then fall on the clone's head, knocking him out thanks to him being weakened.
- Foreshadowing: Dupe's first example of their powers is when they clone Lilo's lollipop to which she notes that the cloned lollipop is low-cal. The end of the episode has Dupe's job with a ice-cream vendor who makes low-fat copies of people's orders.
- He's Back!: Under the effect of Dupe's duplicating ability, Stitch spends most of the episode tired and weak from only having a fraction of his strength. When Lilo reunites him with his clones, she asks if he's back to his original self. To this, he replies, "The one and only."
- Hope Spot: Lilo thinks the other girls have finally shown up for her slumber party, with four shadows seen against the door. It turns out to be Yin, Yang, Richter, and Cannonball answering Stitch's invitation.
- Insult Friendly Fire: While discussing his bad day with Reuben, Gantu calls Stitch a "trog", only to realize that the term also applies to the experiment currently lending him a friendly ear.Gantu: It's that trog... he's always besting me! I can't take it anymore! ...Er, you're not offended when I call him a trog, are you? Because after all, you're a trog.
Reuben: Please, don't you worry about me. This is about you. - Jerkass Has a Point: Although brusque and discouraging on paper, Reuben isn't wrong to point out that Gantu wallows in a lot of self-pity and blames Stitch for all his misfortunes one too many times.
- Mundane Utility: At the end of the episode, Dupe's job is to help make low-fat snow-cones.
- Not-So-Harmless Villain: With his own squad of experiments backing him up, Gantu becomes much more dangerous and effective.
- Our Clones Are Different: The titular experiment (number 344) generates a ray from his head which clones anything it hits, whether that be a living being, or an inanimate object like confectionary. Dupe's ray can clone a target once or a hundred times in a single hit, and he can reverse the process (merging the clones back into the original) just as easily. An unintended and debilitating side-effect of the cloning is that the original template's strengths, rather than being replicated within each of the clones in the same amount, are instead siphoned off from the original and divided mathematically amongst them and their clones: cloning a lollipop once results in both versions having only half their normal calorie count, cloning Stitch three times means that all four Stitch's only have 25% of the original/whole Stitch's strength and stamina, and cloning four other experiments a hundred-fold each results in the clone army being so individually weak that a mundane exhalation of breath can knock them over like twigs.
- Pet the Dog: Reuben sincerely offers to listen to Gantu's complaints, though he ends up regretting it upon hearing how whiny it all is. Reuben opts to listen again at the end of the episode.
- Series Continuity Error: Hammerface already appeared in "The Asteroid", where he was already activated and on the good side.
