Mountain man is a mysterious stranger that the study group encounters in the wilds of Colorado. A former alumni of Greendale, he had decided to live a much simpler life forsaking the trappings of the modern world (although it's implied by Jeff that he wears a wig). Mountain man's first and only appearance was in the Season Four episode "Intro to Felt Surrogacy". He is portrayed by actor Jason Alexander.
In the study group's fourth year at Greendale, they decide to get out of the rut they felt they sank into at school by taking having an adventure off campus. However, the hot air balloon trip they decide to take together goes awry when the vehicle lifts off prematurely due to Pierce and Troy fiddling with the controls. The balloon takes off and drifts away ultimately crash landing into a forest. Struggling to get their bearings, the group is surprised by the sudden appearance of a Mountain man. The stranger deduces they are Greendale students due to a polo shirt Pierce was wearing embroidered with the school's name. He explains he used to go there himself before deciding to live in the forest and be free. Jeff isn't that surprised to see an alumni of Greendale is a transient mountain man but Troy is intrigued. He asks the Mountain man if he misses having stuff to which he replies that out here you have everything you need. The study group later recounts this chance meeting to Dean Pelton during puppet therapy and relate what was said by the Mountain man through song:
The Mountain man hands out berries to the study group which turn out to be psychotropic in nature. As they all start tripping out, the Mountain man waves goodbye to them and says "Be free my friends, be free!" before leaving them and heading back into the forest never to be seen again.