"Hunkahunka Burnin' Angel" is the fourteenth episode of Stitch!-The Mischievous Alien's Great Adventure.
It's Valentine's Day on Izayoi Island, and Angel is coming back to the island to visit her valentine Stitch, who buys her a very large amount of presents. Yuna, Sasha, Pleakley, and BooGoo are walking down the sidewalk talking about who they chose for their valentines when Stitch runs past them and meets Angel at the dock. The four watch as Stitch accidentally trips and drops all the presents; one that held a cake falls right on top of Angel. Stitch licks the cake from the top of her head, but she rejects him and angrily storms off. Stitch is left alone and depressed when Yuna and the others walk up and Pleakley tries to cheer him up by saying at least he didn't come up with an evil plan to get Angel back like using Hunkahunka. After hearing this plan, Stitch smiles and runs off to do it.
He goes to Jumba's lab and while he's not home, he sees an object under a tarp. Ignoring the note that says "Please not to Touch", he takes off the tarp and uncovers an imcomplete teleportation device. Seeing that this could work for his plan, he finishes building it and uses it to transport Experiment 323, Hunkahunka, directly to him.
Running to stop Stitch before he can do this mischievous deed, Pleakley explains Hunkahunka's power to Yuna and Sasha: whoever he pecks falls in love with the next person they see.
Angel is relaxing in a chair on the beach. Stitch runs up to her with Hunkahunka in a pink birdcage and opens it. The experiment pecks his once-fellow captive and she falls in love with Stitch, seeing him as her Prince Charming. Pleakley, Yuna, and Sasha catch up to Stitch, but they're too late. Pleakley tries to tell Stitch that this is a bad idea, but he doesn't listen.
Later at Yuna's house, she, Pleakley, and Sasha start making Valentine's chocolate while Angel makes a place for Stitch to sit, gets a drink for them to share, and dresses him up in different outfits. He starts gloating about how awesome and cool he is and Angel asks to go on a picnic, which he happily agrees to.
As they have their picnic, Kenny, Ted, and Marvin are walking along and the former is sad because he doesn't have a valentine. Ted and Marvin try to cheer him up, but he angrily denies that nothing is wrong. Ted then sees Stitch and Angel and Kenny can't believe that Stitch has a valentine and he doesn't. Stitch calls himself the "love guru" and offers to help him.
Yuna, Sasha, and Pleakley are squeezing the chocolate they made into their pans. Stitch and Kenny secretly watch and the latter marvels at how pretty Sasha is. Stitch lets Hunkahunka out again and he pecks Sasha when nobody's looking. Since Kenny has to be the first person she sees, Stitch shoves him into the house and he knocks over the table where the three were working on the choccolate, ruining it. Yuna and Pleakley get mad at him for that, but they forget about it when Sasha declares her newfound love for him. They head off to the beach together. Yuna figures out that Stitch made this happen and demands that he turn Sasha back to normal, but he refuses, saying that he's doing a good deed. Angel walks up and asks to go to a pool with him. Stitch complies and the two drive off in his space cruiser.
In his asteroid base, Hamsterviel watches the escapade and demands Gantu and Reuben to go with him to the island to catch Hunkahunka. Reuben correctly guesses that he just wants the experiment to get girls, but he denies it and the three fly to Earth, only to get hit by a smaller asteroid.
Yuna and Pleakley enter Jumba's lab to find the file that states how to reverse Hunkahunka's effect. Pleakley tries to get on Jumba's computer, but he accidentally sets off an alarm and gets trapped in a big round glass case. A beam is transferred into him which turns his whole body big and round like an orb. He falls out of the case and smashes out of the house.
Meanwhile, at Penny's house, she is relaxing in her Olympic-sized pool, but Stitch and Angel arrive. She angrily tells them to get out, but then she sees Hunkahunka and takes him, declaring that anything cute and pink is hers. The cage pops open and he flies out; Stitch tells him not to peck Penny, but he doesn't listen. Penny tries to avoid getting pecked until Stitch picks her up and runs up a tree, but he drops Penny, runs back down, she falls on top of him, and Hunkahunka pecks her, causing her to fall in love with Stitch. Penny chases him, but then the orbified Pleakley bounces onto the scene and Stitch jumps on top of him to get away from the lovesick girl.
Kenny and Sasha are walking through the forest and Sasha asks Kenny to call him before he goes to bed. Kenny agrees, but then Sasha asks him to call her seven times before that, making him uneasy.
Penny and Angel are running after Stitch, still escaping on top of Pleakley. Yuna sees them and tries to run away, only to get flattened. Penny uses Yuna as a stepping stone to jump up at Stitch, but the alien grabs a branch and hangs there while Penny lands on top of Pleakley and rolls out of the scene. Stitch is alone with Angel again and he fears she's going to kill him for Penny loving him, but she's not mad at all, which makes him concerned. He gets another cake and smushes it on her head again, but again she doesn't get mad. Yuna comes to him and asks him if he likes Angel being sweet like this. Stitch says no and that he preferrs Angel the way she used to be: sassy. He agrees to undo the effect, but loud stomping is heard and a giant robot walks up to them.
On the beach, Hamsterviel, Gantu and Reuben have set up a simple animal trap with a sandwich as bait. Hamsterviel tries calling Hunkahunka to it with no effect. His two henchmen discuss the things they could be doing instead of wasting their time like that.
Back with Stitch, Yuna, and Angel, the robot is piloted by Jumba, who's finally returned. Yuna asks him how to reverse Hunkahunka's effect, but before he can say it, the experiment comes and pecks him, causing him to fall in love with Stitch as well. Ted and Marvin then enter running from Kenny, who's in turn running from Sasha, who has become overly obsessive. Hunkahunka pecks all four of them as well. Penny and Pleakley come back and the bird-like alien pecks Pleakley, shortly followed by Yuna. Stitch runs from everybody until they come back to Penny's pool and everyone falls in. Since the antidote for the love sickness is common water, everyone is cured. Angel is mad at Stitch again, Kenny runs in terror from Sasha, and Pleakley complains that he's still a big round blob.
Back at Hamsterviel's sandwich trap, Hunkahunka takes the bait and is trapped. Gantu reaches down to grab him, but Hunkahunka pecks him and he falls in love with Hamsterviel.
Stitch loses a couple of his good deeds and regrets the mess he caused. He puts the finishing touches on a cake he made for Angel and rushes to deliver it before she leaves. He almost drops the cake on her again, but catches it. He gives it to her, but she takes it and smushes it on his head, shortly leaving afterwards. Stitch is happy that his boojiboo is back to normal and eats the ruined cake.