The PJ Masks and George and Harold become bored with their very easily outmatched competition, so they team up and create a villain to fight. Their villain won't be evil and refuses to destroy him. Eventually, he does in turn attack Piqua from feeling neglected after The PJ Masks and George, Harold and Erica abandoned him. Now the villain is putting citizens of both worlds into his own, alternative world like where he was born in and creating vacuums that would destroy the worlds where he has control over and is planning his revenge against The PJ Masks and George, Harold and Erica for abandoning him like that.

Needing to be cool, George, Harold, Erica and Captain Underpants return to Tarabiscoville but this time they take the M.I.S.F.A.R.T.S with them. There, they challenge the PJ Masks them in a hero competition, But a problem arises, the Evil Blowing Balls from George and Harold's comic are up to stop the Earth's rotation to make Friday the 13th last forever. Romeo wants to blow up the universe and after seeing Captain Underpants, he decides to go to Captain Underpants's dimension to get help with his plan. He ironically gets Melvin Sneedly, the school tattletale scientist.

Part of the villainous asteroid filled with the evilness, went through the portal and into Piqua, and Melvin Sneedly got it and gains its powers. George and Harold found out weeks later, they and their friends team up with the PJ Masks: Power Heroes to stop Melvin.

A chaotic duel with characters from The Epic Tales of Captain Underpants and PJ Masks erupts when George, Harold, Mr. Krupp and Erica got send to a other dimension which just happens to be in Tarabiscoville, The PJ Mask's HQ, but Catboy, Owlette and Gekko accidentally teleports themselves into George and Harold's dimension. Now the heroes are stranded in each other's worlds. Now George and Harold must shut down PJ Robot, who George uploaded a destructive video game into, before he destroys Tarabiscoville. Meanwhile, The PJ Masks must stop Melvin Sneedly from taking over Piqua.