Samuel Herbert "Serious" Stone, more commonly referred to as Serious Sam or just Sam, is the titular protagonist of the Serious Sam series. After he inadvertently awoke Mental from is millenia-long slumber, he works himself in the ranks until he reaches Captain in the Earth Defense Force, a small military organization who defended themselves against Mental's alien army during the Mental War, and fights alongside his comrades against the invaders, becoming a legendary hero for mankind.