Experiment 626, otherwise known as "Stitch," is a mischievous blue alien with a level of strength far beyond his small size. While roaming the far reaches of outer space, Stitch's spaceship gets sucked into a storm, causing it to crash-land onto Izayoi Island, Japan. He is found by a young girl named Yuna, but the two do not get along very well until Stitch ends up saving her life during a thunderstorm.

From that point onward, Yuna and Stitch become inseparable, spending time together, having fun and dealing with the consequences of Stitch's antics. Eventually, the pair are discovered by Stitch's fellow alien friends: Dr. Jumba Jookiba, the self-proclaimed "evil scientist" who created Stitch, and Pleakley, the leading expert on Earth's culture. Having found Stitch at last, Jumba and Pleakley join the two, filling their days with an abundance of Japanese culture and high-tech mishaps.

[Written by MAL Rewrite]