Marcel is Ross's pet monkey on the TV show Friends. This monkey was fairly significant as it is one of the only cases in television history of a show introducing a monkey as a character without going off the air soon afterwards. Normally when a television show introduces a monkey it is doing something called jumping the shark in a desparate grab for ratings. These shows usually don't get renewed, but friends went for many seasons after the monkey was gone.

Marcel is important because he caused Ross to realize that he could be a good father. Ross had been questioning his ability as a parent, when Marcel swallowed a scrabble tile and nearly died. Ross handled the situation perfectly.

Ross had to eventually give Marcel up for adoption, because he had reached sexual maturity and would not stop humping everything in sight. You just can't do monkey humping jokes for more than a single episode.

So Marcel goes to live at the Zoo. A later on Ross goes to visit Marcel at the zoo and is told that he has died. But he finds out from a janitor that Marcel was actually sold to a movie studio.

Ross later got to see Marcel one last time on the set of a movie Marcel was in, "Virus 2 : The Virus Takes Manhattan".