What movie is 10/10, yet hardly anyone has heard of it?

The Man From Earth.

It's about a history professor that suddenly decides to quit his job and move away. His fellow professors decide to leave the party, and during that time they ask him why he's leaving. He decides to tell them he's 14,000-years-old, and he has to move on when people realize that he doesn't age. That's not giving anything away about the movie, even if it seems like it is. It's an absolutely fantastic movie, where they try to decide if he's crazy, or if he's telling the truth.