The games form a trilogy with a continuous story throughout each. Although Arc is the primary protagonist, each game features a new lead character. Arc the Lad sets the stage for the next two games and follows Arc and Kukuru as they discover a plot to restore the Dark One. Arc the Lad II introduces Elc, a young Hunter that becomes tangled in the plot and eventually joins the battle against the Dark One. Arc the Lad III features Alec, a young Hunter with a mysterious past.

Each game expands on the previous one. Arc the Lad II features a much larger and less linear world than its predecessor, and it brings back the cast of the first game in addition to featuring a new group of characters. Arc the Lad III features an upgraded graphics system, replacing the sprite backdrops of the first two games with three-dimensional backgrounds.