The Incredibles. He is voiced by Jason Lee.
As a young Buddy Pine, the boy who would become Syndrome aspired to become a superhero and this goal led him to beg Bob Parr to hire him as a sidekick, "Incredi-boy!". Sadly, after Bob categorically refused to grant Buddy's favor, Buddy returned home in disgrace and rejected the righteous path. He became embittered and eventually descended into megalomania.
Buddy is apparently possessed of a technical genius, and even at an early age could create wondrous gadgets to circumvent his lack of "super" powers. After his dismissal at the hands of Mister Incredible, and the dissolution of classical superheroes, the young man turned his gifts towards evil, eventually murdering dozens of superheros with his Omnidroids and various super weapons. He is a classical sociopath, caring not at all for the rules of society; and seeing it as his mission to make himself the world's ultimate hero through trickery and technology, and when he grows tired of that, to make superheroes entirely obsolete by selling his weapons to the highest bidder. Because "when everyone is super... no one will be."