Mr. Nesmith is an intelligent American chimpanzee and Jimmy's Planet Sheen counterpart. Apperently his brain cells have been enhanced after he broke into Zeenu's atmosphere. He seems to be a replacement for Jimmy. There's way more to this chimp than a name tag. He is a master of all things intellectual including math, science and sudoku. He has been camping out on Zeenu since his rocket crashed there back in the '60s. Nesmith always tries to warn Sheen of the consequences of his selfish and dumb choices, but Sheen doesn't listen and does what he wants instead.
He first met Sheen when he landed in a cave and the two decided to form an alliance and repair Jimmy's rocket so they can return to Earth. Throughout the series, Nesmith keeps trying to repair the rocket and find things that could possibly get them home.
Mr. Nesmith is brown and tanish. He has white eyes with black pupils, gray boots, and a red hat. His spacesuit is white with blue and red lines and the planet Saturn on it. Nesmith has brown arms, a peach nose, and two ears.
- Mr. Nesmith is based off of Michael Nesmith of The Monkees. His similarities include wearing a wool cap and being a monkey like the real Mr. Nesmith did.
- Mr. Nesmith is Jimmy's Planet Sheen counterpart, but he is more paitient and less irritable than Jimmy.
- Mr. Nesmith should be either dead or nearing his final years since chimps live to be 40 to 60, but his increased intellect may come into play, which could expand his lifespan.
- Once he gets to Earth he should become as smart as a regular chimp, unless the Zeenuian air is only needed to be whiffed to have an everlasting intellectual upgrade.
- He is similar to Ape from the George of the Jungle franchise.