It features a Japanese girl named Yuna Kamihara, who takes the place of Lilo Pelekai as the best friend of the titular Stitch, and is set on a fictional island in the Ryukyus off the shore of Okinawa called Izayoi for its first two seasons, replacing Kauai, Hawaii, then moving to a fictional Okinawan city called New Town for its third season.

~Itazura Eirian no Daibōken~) aired in Japan from October 13, 2009, to June 29, 2010, with another post-season special on August 8, 2010, completing Madhouse's 56-episode run.

~Zutto Saikō no Tomodachi~), was produced by Shin-Ei Animation and aired on TV Asahi from July 6, 2010,[2] to March 8, 2011, with a post-season special for this season on June 19, 2011.

He had stolen a space scooter from his creator Dr. Jumba Jookiba and reverted to his destructive programming in Lilo's absence.

Jumba crash-lands on an asteroid in one of Saturn's rings, where he reunites with Pleakley, who had been stranded there while out on a mission about two weeks prior to the anime's events.

There he meets Yuna, a tomboyish girl who lives with her grandmother, practices karate, and whose marine biologist father is long out at sea working on his job.

Meanwhile, Stitch's old nemesis and Jumba's former partner-in-crime Dr. Jacques von Hämsterviel is at large, living in a laboratory hideout hidden on an asteroid along with Gantu and Experiment 625/Reuben, both of whom were re-hired by Hämsterviel after having been discharged from the United Galactic Federation in the interim between the events of Leroy & Stitch and this series.

However, the Spiritual Stone eventually uses its power to destroy the helmet, bringing Sparky back to his previous friendlier self, thus allowing him to resume being one of Stitch's closest "cousins".

Finally, Experiment 624/Angel, who has become an intergalactically popular singer in the time after Leroy, reunites with Stitch after somehow finding out where he now lives.

The two resume being a romantic couple, with Angel making visits to the island during breaks on her concert tour to continue her relationship with Stitch.

Stitch successfully defeats Hämsterviel, returning the Spiritual Stone's power to it, and sends him, Gantu, and Reuben to galactic prison.

However, Stitch is returned to his original strength afterward, much to his dismay, as he still needs to do more good deeds to keep the "ultimate power".

During the villains' time in prison, Hämsterviel finds a strange, purple, female, insect-like alien with shapeshifting abilities, and sends her to Earth to break Stitch's good deed counter.

When Jumba repairs the counter, he and Pleakley find the purple alien and discover that it was brainwashed by Hämsterviel.

After undoing the brainwashing and fixing Stitch's counter, the insect becomes the aliens' new pet who Pleakley names "BooGoo", as she is only able to say the words, "Boo goo!"

Additionally, more experiments, both originating from Lilo & Stitch: The Series and newly introduced to the franchise, appear from this season onward, with most of them now inexplicably under Hämsterviel's possession.

Although Stitch seemingly dies in the explosion, he survives thanks to the Spiritual Stone teleporting him back to Earth and to Yuna.

Hämsterviel, now living on a space station orbiting Earth with Gantu and Reuben, partners with an evil alien woman named Delia, who desires to retrieve a power cell within Stitch called (only in the Japanese version) the "Neo-PowerChip" so she can create a powerful experiment of her own.

Lilo, now an adult with a daughter of her own named Ani, also returns in one episode of this season for a brief reunion and reconciliation with Stitch.

Stitch's friends revive him through their love and support of him, overcharging his power cell, and he overpowers and defeats Dark End, saving the world again and sending Hämsterviel, Gantu, and Reuben back to galactic prison along with Delia.

Perfect Memory, Stitch and Pleakley go out on missions assigned to them by the United Galactic Federation, finding out Hämsterviel, Gantu, and Reuben are behind more crimes.

The series was edited and localized for younger international audiences, especially those in the Western world and the Anglosphere, and a lower TV rating.

[8][9] The first season also aired on Finland's Disney Channel beginning from 7 June 2010, subtitled in Finnish with the English dub.

On August 12, 2022, Disney+ added English-translated subtitles to all episodes, marking the first time that the series' original Japanese production was subbed, although it remains restricted to Japan and Singapore on the service.