Disney/Pixar's 2004 superhero adventure The Incredibles features one of the most memorable movie villains of all time in the form of Syndrome. The former fanboy of Mister Incredible turns to evil after being rejected by his idol, becoming a fearsome weapons dealer with a plan to eliminate and replace all superheroes. While Syndrome is widely beloved for his humor, charm and menace, there was a time when he was originally going to only be a minor character in The Incredibles, as Brad Bird's original idea for the film featured a completely different villain named Xerek.
While not much is known about Xerek, the bonus features on the DVD for The Incredibles provide some insight into Bird's ideas for him, as does the book The Art Of The Incredibles. Xerek was originally intended to be a short, decrepit criminal mastermind with a plan to take down superheroes everywhere using his army of henchmen and robots. Along the way, Xerek ended up reimagined as a tall, dark and mysterious figure similar to a prototypical James Bond villain.
In the years since The Incredibles' release, a few minor pieces of information regarding Xerek have been unveiled to the public. These include the reveal that Xerek was apparently going to be portrayed as an obsessed ex-boyfriend of Helen's, while other early scripts supposedly featured him as being on the side of good at the end of the film. He was going to preside over Nomanisan Island with Mirage at his side, and was also going to use the Omnidroids that ended up as the focal point of Syndrome's plan.
Interestingly, Syndrome was actually a part of Brad Bird's original pitch for the film, but he was going to serve as a rogue supervillain with a fairly minor role towards the beginning of the story, similar to the part Bomb Voyage plays in The Incredibles' final product. He was intended to attack the Parr family after discovering Mister Incredible's secret identity, eventually perishing in an explosion, but Syndrome proved to be so popular among the film's crew that he was eventually elevated to the role of the main villain. This led to Xerek's role being scaled back and ultimately removed.
Despite the fact that he was cut from the film, Xerek ended up getting a second chance in Boom! Studios' comic book series that served as a sequel to The Incredibles. He is depicted as the main villain of the comics, retaining his status as Helen's ex-boyfriend as well as his original decrepit physicality, which is explained by his previously having used a machine to artificially extend his lifespan. As part of a sinister plan, Xerek puts together a team of supervillains called the Unforgivables, but the comic series was unfortunately canceled before his endgame could be revealed. Incredibles 2 eventually released and rendered the events of the Boom! Studios series non-canon, once again erasing any trace of Xerek from the Incredibles universe.
Ultimately, The Incredibles most likely ended up far better off with Syndrome as the villain than it would have been with Xerek. While the mystery surrounding his character is interesting, it's likely that Xerek ultimately would not have ended up being as dynamic as Syndrome, especially considering the latter's outwardly boisterous and attention-seeking personality. The "mysterious and rich criminal mastermind" is an undoubtedly overused character archetype in action movies, so the choice to go with a rejected sidekick turned out to be a bold, dramatic and ultimately far more memorable option.