Charles F. Muntz

Charles F. Muntz is the main antagonist of Up, and a minor character of The Secret of UglyDolls and Up.

Official Description
At the peak of his career, Muntz was a charismatic, smart and daring young man whose spirit inspired countless fans to look for adventure.

However, Muntz's quest for the bird that caused his disgrace destroyed him, as his search turned to obsession. Now a ghost of his former self, he became a heartless man, consumed by bitterness, paranoid to the extreme, and convinced that anyone who comes across him is after the bird. It is implied he killed two explorers already, and was intending to do the same with Russell and Carl. It is shown that Muntz's obsession is such that he doesn't care anymore for the rest of his collection, showing no hesitation to destroy some of his unique specimens when trying to take down Carl.

Muntz largely serves as a parallel to Carl. He was a man broken because he lived obsessed with his former existence and desperately trying to relive it at any cost, showing what Carl could have become, had he not learned to accept the loss and move on with his life.