Charles Muntz (voiced by Christopher Plummer) is the main antagonist of Jaden goes Up. He is a famous explorer who went to Paradise Falls to find an interesting bird for fame and glory, and he's never returned. When Carl Fredricksen, Russell, and Jaden and his team met him, they were at first welcomed as guests to Charles, but Charles had a suspicion that they were after the bird, which Russell named "Kevin." Charles sent his dogs after them, and managed to capture Kevin. But after a battle on his blimp, Charles caught his leg caught on some of the balloon strings that lifted Carl's house. The strings snapped and he possibly fell to his death.
- Charles Muntz will become Jeffrey's enemy in Jeffrey & Friends go Up. After this, he will form his own villain group called Charles Muntz's Empire.
- He doesn't join Set because he doesn't trust his methods. Set and his recruits and Charles Muntz's Empire join forces briefly in Jeffrey, Jaden & Friends' Storm Adventures of Justice League Unlimited.
- Charles Muntz will guest star in Jeffrey, Jaden and The Adventures of TinTin (2011).