Fullmetal Alchemist: Brotherhood is set in a fictional world where alchemy – the transmutation of raw materials into objects – is science, and the way of life. The series follows the Elric brothers, Edward and Alphonse, on their perilous journey in search of the legendary "Philosopher's Stone". They set forth hoping that the magical artifact can restore their bodies after a failed attempt to revive their dead mother cost Edward his left leg and right arm, while Alphonse's entire body was taken away leaving his soul affixed to a suit of armor.

Source: Anime News Network