"Long ago in a distant land, I, Aku, the shape-shifting Master of Darkness, unleashed an unspeakable evil. But a foolish samurai warrior wielding a magic sword stepped forth to oppose me. before the final blow was struck, I tore open a portal in time and flung him into the future where my evil is law. Now the fool seeks to return to the past and undo the future that is Aku! "
Samurai Jack is the story of a Japanese prince whose father’s empire was destroyed by Aku. SJ escaped and trained to become a Samurai and was given a katana, a magic sword capable of slaying the demon.
He returned home and freed his father and challenged Aku to a duel, but just before SJ can beat him, Aku opens up a portal in time and sends SJ to the future.
Samurai Jack found himself in a land and time where Aku had triumphed and along with his evil robots, rule the earth.
His mission is to find a way to travel back in time, kill Aku and prevent the Master of Darkness from taking over the earth.