The movie entitled Stitch! The Movie is about the adventures and experiments of Dr. Jumba. Stitch is having a hard time adjusting to the conditions on Earth. Lilo encourages him to stay positive and focused by telling him how special he is. This however does not make him feel better about himself as he instead feels worse than before.
Stitch and Lilo are together upstairs one night when they hear a crashing sound from downstairs. They rush down where they meet Gantu struggling to break into their house. When Gantu sees that he has been caught, amid all the confusion he finds and picks up a blue ball after which he forcefully takes Jumba away for questioning.
Lilo and Stitch decide to pursue Gantu as he was taking Jumba away by using Jumba's ship which they found close by. They chase Gantu all the way into space and they start a fight with Gantu after which they fall back to Earth.
Lilo, Stitch and Pleakley locate a container which Jumba was hiding in the house. Pleakley suggests that it contains some of Jumba's experiments but was storing them in dehydrated form. Pleakley therefore warns Lilo and Stitch not to put them in water as he believes this will destroy the experiments which Jumba had suffered to generate.
However, Lilo and Stitch intentionally put them in water and the Experiment 221 vanished. Jumba on his part is now held as a prisoner in Dr. Hamstervel's ship. Harmstervel is an alien who always tries to intimidate Jumba while in the ship but fails. He then decides to activate Experiment 625 and use it to attack Jumba. The activated experiment instead works in Jumba's favor as it is characterized by the same attributes as Stitch which is laziness and cowardice.
Pleakley succeeds in locating Hamstervel's ship and get into an agreement to give him Experiment 221 in exchange for Jumba after a series of figts in the ship they are able to set Jumba free and Hamstervel is arrested.