Stitch becomes egotistical after beating his experiment catching record, so Jumba decides to teach him a lesson by activating his brand new experiment, 627. Being more powerful than Stitch with none of his weaknesses, Stitch may meet his match when 627 escapes Jumba's custody and falls into the hands of Gantu. 627 works for Gantu capturing experiments and proves unbeatable until Reuben, who's had enough of 627's abuse, calls Lilo and reveals that 627's weakness is laughter. Lilo and Stitch use this to defeat 627, and as it is impossible to turn him good, they use a dehydrator to turn him back into a pod. However, Jumba is shown to have an Experiment 628 whose pod he stores on his ship.
- Moral: If you want to feel good about yourself, be humble and don't let success go to your head.
- 627's creation was oddly foreshadowed at the end of Stitch! The Movie.
- 627 is the only experiment in the series that could not be rehabilitated and the only one that was never given an actual name, yet he was nicknamed "Evile" by certain fans.
- Ironically, although Jumba said it was impossible to deactivate 627, Jumba was able to deactivate the other 625 experiments that were created before 627, excluding Stitch.
- When Stitch taunts 627, he stands on his head with his two hands flat on the ground and shakes his rear end, a callback to the first film. However, Stitch's butt is slightly overscale in this episode.
- 627's manner of defeat is similar to the Toon Patrol from Who Framed Roger Rabbit, though while most of the Toon Patrol die from laughter, 627 just passes out long enough to be dehydrated.
- In spring 2004, Disney Channel held an online poll that asked viewers for their favorite experiments and episodes from Season 1 of the series. According to the top 10 results of that poll, "627" was the #5 most popular episode and experiment.