Mertle gets a new charm bracelet for her birthday, but Lilo and Stitch find out that one of the charms is the pod of an experiment that can create black holes. Lilo gets into trouble with a local police officer as she tries to take the pod before Mertle gets it wet. Meanwhile, Nani is cleaning up her rental hut for an upcoming inspection.
Lilo and Stitch are playing on Lahui Beach when they knock over a jewelry stand, prompting local Police Officer Kahiko to call Nani to take them home. After she does so, Nani tells Lilo to avoid getting into further trouble as she needs to impress a rental company inspector who wants to work with the Rental Hut when they visit it soon.
Mertle invites all the hula girls except for Lilo to her birthday party, prompting Lilo to pull a prank on the redhead by pretending to be a monster, which all goes wrong when Stitch notices the coconut cupcakes and rushes to eat them all. When Mertle confronts her, Lilo notices an experiment pod on Mertle's new bracelet and tries to grab it from her, but Mrs. Edmonds then comes out and notices the mess—and Lilo attacking her daughter. After Nani takes Lilo home again, the little girl tells her older sister about the pod on Mertle's bracelet, saying that she didn't even see the number on it, but Nani reiterates to her sister that she needs Lilo to stay out of trouble.
Lilo and Stitch then try to investigate the pod on the bracelet by having Stitch infiltrate Kokaua Town's pet shop where Mertle and her posse are visiting. As he pretends to be a rabbit in front of them, he relays to Lilo that the pod is of Experiment 606, which she discovers is a black hole generator. She tells Stitch to relay the info back to Jumba, but then Officer Kahiko notices Lilo in his car. He takes her to the local police station to have Nani come pick Lilo up. Shortly afterwards, Stitch comes to the station after telling Jumba back at home about 606 and "breaks" Lilo out of jail. (In actuality, Lilo wasn't locked in the cell; she just left herself in it.)
Everything seems to be going smoothly during the Rental Hut inspection until Mertle drops by asking Nani for a surfboard, and Lilo suddenly comes in and tries once again to take the pod from Mertle. Lilo tells Stitch to take it from Mertle, but he ends up destroying the Hut in the process. As Nani takes Lilo back home, she shouts at Mertle not to put the bracelet in water. It's from there that Mertle finally notices the pod on the bracelet, so she goes back to her home and drops the bracelet in a glass of water. 606 activates and turns into a black hole, sucking up everything in Mertle's bedroom.
Back at the Pelekais' home, Nani is distraught from what happened at the Hut and upset for probably losing her raise. Lilo asks for her help in dealing with the experiment, saying, "What good is a raise if the whole world gets sucked in by a black hole?" Nani says that she can't and has to return to her boss Mr. Wong to beg him to keep her under his employ. Just after Nani leaves, Lilo gets a phone call from Mertle demanding her to come deal with the black hole. Lilo and Stitch round up Pleakley and Jumba, the latter alien who made a special gun designed to fire an "anti-antimatter sphere" that will cause the black hole to collapse, and they drive in the X-Buggy to Mertle's house.
The black hole is now hovering over Mertle's house and has grown to be large enough to suck in cars and houses. Lilo and Stitch convert the X-Buggy into flight mode and enter the black hole. Meanwhile Nani, goes see Mr. Wong back at the destroyed Rental Hut, but to her surprise he says that they passed the inspection, but the rental company wanted too much money from the Hut, so he turned down the deal. Nani then goes to see her sister, promising Mr. Wong that she will return to help repair it.
In the black hole, after having some trouble firing the gun, Stitch throws the anti-antimatter sphere into the event horizon, which successfully causes the hole to collapse. Lilo and Stitch barely manage to escape the collapsing hole, and all the items that were sucked are returned. Nani is relieved to see her sister is safe, though she also saves Lilo from being crushed by a falling car.
The Pelekai ʻohana helps to reconstruct the Rental Hut, with 606 (now named "Holio", but we never hear anyone call him that in this episode) clearing out leftover debris. Lilo tells Officer Kahiko, who grills some steaks for them, that she is now "completely rehabilitated". The pleased officer asks her if she wants a burger, then Pleakley suddenly makes requests for a lot of food as the episode ends.
Experiments who appeared or were mentioned in this episode:
- Holio (X-606): This episode's Monster of the Week; a small, red chipmunk-like experiment with a wide and large mouth, two thin antennae, and three thin back spines who is designed to create a matter-sucking black hole when he opens his mouth.
- Richter (X-513): He makes a brief cameo at the end of the episode, helping Nani to reconstruct the Rental Hut.
Tropes featured in this episode:
- Abnormal Limb Rotation Range: Pleakley is... very flexible with his yoga.
- Be Careful What You Wish For: When Mertle demands to know where he doll collection is from Holio, he gives back to her...by spitting the dolls right at her.
- Big Eater: Pleakley, of all people, in this episode. After spending much of the episode focusing on doing his weird yoga, once he returns to his old panicky self, he becomes very hungry for a lot of meat foods, probably because he hasn't been eating anything since starting his yoga.
- Black-Hole Belly: Turns out that Holio can retrieve the items he sucked up, as seen when he spits out Mertle's large collection of dolls.
- Crazy-Prepared: Thanks to Stitch telling him about 606 earlier, Jumba quickly creates a special gun to deal with the black hole.
- Delicious Distraction: While he and Lilo are pretending to be a monster, Stitch looks through a hole in the Edmonds' fence and sees the coconut cupcake that Teresa dropped, causing him to immediately ruin the monster act by bursting through the fence and eating all the cupcakes.
- The Inspector Is Coming: The B-plot of the episode is Nani trying to fix up the Rental Hut for an upcoming inspection so she could get a pay raise, but Lilo getting into trouble is making it difficult for her to do so.
- Line-of-Sight Alias: Lilo tells Mertle and her friends a story about a monster that eats people (and birthday cakes) in an effort to scare them after Mertle didn't invite Lilo to her birthday party. When Lilo gets to the name, she spies a gecko clinging to the post of the hula halau, which then licks its eye, giving her the name "Geckoliki".
- Never My Fault: Even though Mertle is the one who activates 606, despite Lilo's warnings, she blames Lilo for it.
- Not So Above It All: Throughout the episode, Pleakley has acted virtually unfazed by anything thanks to his new lifestyle of yoga and a vegetarian diet. But upon hearing from Lilo that Holio has been activated and has created a black hole, he panics and falls back on having a filling meal of steak.
- Oh, Crap!: Lilo has this appropriate reaction upon learning that the experiment pod on Mertle's bracelet can create a black hole.
- One Phone Call: Lilo demands one when she pretends to have been arrested. Kahiko says he's already called Nani for her.
- Skewed Priorities: Pleakley lampshades his. He was focused on tranquil meditation when the world was in danger of being swallowed up by a black hole.
- Tempting Fate: Played with after Kahiko tells Lilo he is taking her to the station:Lilo: OK, but I think it's only fair to warn you. I will definitely try to escape. You should probably put on the siren.
Kahiko: Mm-hmm... (buckles his seat belt) Buckle up, please.
Lilo: (buckles her seat belt) Don't think these bonds can hold me. (Gilligan Cut to Lilo behind bars at the station) I know my rights! I demand a lawyer!
Kahiko (reading a newspaper): Lilo, you're not under arrest. Come out of there before someone sees you. - Title Drop: Averted; 606's new name does not get spoken by anyone in this episode.
- Too Dumb to Live: When Lilo learns that 606 is a black hole that could bring about The End of the World as We Know It, she tells Mertle not to activate it. And what does Mertle do? Put her charm bracelet in water!
- Unrealistic Black Hole: Holio's black hole looks like a red vortex and seems to be unable to suck up blissfully unaware people like Mertle's mother.
- Vacuum Mouth: Holio has a powerful one to say the least. Fortunately, after Lilo and Stitch stop his black hole, he uses his powers to clean up debris.
