Mr. Mojo’s Rising (1999) — The Powerpuff Girls Cartoon Episode Guide
It’s a blast from the past– a blast of Chemical X that is. Mojo Jojo reveals that he was once the Professor’s assistant, and that he too was altered by the use of Chemical X. But while little Jojo got a big brain, the Girls won the Professor’s heart with their combination of toughness and cuteness.
Jojo left the lab and became Mojo Jojo. Out of guilt, the Professor agrees to give Mojo superpowers like the Girls, and Mojo tries to destroy them with his new-found strength.
The Professor finally remembers that Jojo was a terrible lab assistant, who pushed him, triggering the accident that led to the Powerpuff Girls being on earth! Distracted by the implications of his actions, Mojo goes into a temporary daze. The Professor is able to strap up Mojo to the power-bestowing device, which, luckily, has a reverse button.
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