The most manipulative diabolical plan concocted by the Powerpuff Girls' arch nemesis Mojo Jojo involved the super-intelligent monkey exploiting a crucial part of his origin story that subsequently one-ups his first and then most dastardly plot.
As revealed in the 2002 Powerpuff Girls prequel movie, what actually caused Professor Utonium to accidentally add the superpower-inducing Chemical X to his concoction was his monkey lab assistant, Jojo. The added ingredient not only created the titular Powerpuff Girl but Mojo Jojo as well who received superintelligence from the accident's resulting explosion. In the film, Mojo Jojo exploited the City of Townsville's distrust of the Powerpuff Girls' then-new abilities by pretending to relate to the trio's despair at being rejected because they were special. His ruse allowed the supervillain to trick the Powerpuff Girls into helping him build a weapon to enslave humanity by saying they were creating the fake Help-The-Town-and-Make-It-a-Better-Place Machine.
Years after the film's debut, Mojo Jojo once more resorts to trickery using his origin story as bait except by focusing his efforts on Professor Utonium in IDW Publishing's The Powerpuff Girls by story writer and artist Troy Little, colorist Jeremy Colwell, and letterers Neil Uyetake and Troy Little. Mojo Jojo is able to convince everyone in Townsville that the superintelligence he received from Chemical X has allowed the knowledge of his continuous defeats at the hands of the Powerpuff Girls to haunt him to the point where he would like to become Jojo again by receiving Professor Utonium's Antidote X. Knowing that his former lab partner and owner would get nostalgic, Mojo Jojo constructed an elaborate plan that was based on Utonium bringing him back home and letting him live in the lab where he would eventually regain his memories, re-inject himself with Chemical X and use the professor's inventions that he would now have access to in order to destroy the world.
IDW's series is the perfect sequel to The Powerpuff Girls Movie. It not only expands upon the film's introduction of Antidote X, but has Mojo Jojo essentially try the same thing he attempted in the original series' prequel except this time depending on Professor Utonium's naïveté and guilt. The comic is also much more twisted than its inspiration because Mojo Jojo exploits the much deeper connection he has with Utonium than he did with the Powerpuff Girls in the prequel movie since he had just met them. The only reason why Mojo Jojo could connect with the superpowered trio was that they shared a similar origin story that purportedly affected him in the same way as it did them. He essentially just preyed on the trust and vulnerability of three innocent girls whose only history with him at that point was what he told them. Meanwhile, Professor Utonium not only knew Mojo Jojo before he became a villain, but he was his pet monkey. Mojo Jojo, therefore, capitalized on the memories they shared in the lab together and the guilt Utonium undoubtedly felt for ignoring him after creating the Powerpuff Girls.
Although Mojo Jojo's scheme in the film effectively fits and plays into its themes of rejection and using good powers in a bad way due to inexperience, the Powerpuff Girls comic more successfully connects to the major twist that the movie introduced, which was that Professor Utonium not only knew Mojo Jojo before he became a supervillain but essentially made him and accidentally added Chemical X to his concoction to create the perfect girl because of Mojo Jojo's destructive tendencies as a primate. And how the superintelligent monkey uses that connection to his advantage effectively makes his origin story that much darker than the Powerpuff Girls film ever could.