After capturing all 625 experimental creatures of evil Dr. Hamsterviel and setting them free, Lilo, Stitch, Pleakley, and Jumba are shocked to discover the existence of Leroy - a troublesome clone of Stitch with an unquenchable appetite for destruction. To save the whole universe, Lilo, Stitch and their friends must stop Dr. Hamsterviel's devious plan to form an army full of Leroys.