Doomed to earn the moniker of the Black Swordsman, Guts journeys across many lands as a mercenary, recognized by his colossal greatsword. He accepts the most profitable contracts without committing to any single group until he encounters the Band of the Falcon. Following a mission, Guts is ambushed and defeats several members of the band. Griffith, the band's leader, finds Guts intriguing and challenges him to a duel. While the other members cannot match Guts, Griffith overwhelms him with a single strike.
Left incapacitated, Guts recovers at the Band of the Falcon's camp. Upon waking two days later, he confronts Griffith once more, agreeing to a duel where the loser must join the band. Weakened by his injuries, Guts loses and is subsequently recruited by Griffith.
Over the next three years, Guts rises to become one of the band's top commanders. His prowess in battle is unmatched save for Griffith, as he faces numerous enemies alone. The combination of Guts' formidable strength and Griffith's strategic leadership leads the Band of the Falcon to victory after victory. However, an ominous force looms, poised to alter Guts' existence forever.