The Buried Man is a man who was buried alive in a grave by Gravedigger Billy.
Lisa looked out her window as he is finished being buried by Groundskeeper Willie's cousin, Gravedigger Billy. Gravedigger Billy tells her that if anyone were alive, they'd ring a bell he put into the ground. The buried man than rings the bell. Billy assures a frightened Lisa that it's just the wind. His hand than popped out from the grave. Billy than took his watch and started beating the man's hand with his shovel.