"Drifters" is a historical fantasy anime that centers on the concept of legendary warriors from different eras being transported to an alternate world to participate in an ongoing war. The narrative begins with Shimazu Toyohisa, a samurai from the early 17th century, who, after being mortally wounded at the Battle of Sekigahara, is transported to a mysterious corridor. Instead of dying, he finds himself in a strange new world populated by other historical figures, known as "Drifters," who have also been pulled from their respective timelines.

In this world, Drifters are summoned to fight against the "Ends," another group of historical figures who have been corrupted and now serve a dark, oppressive force. The Ends aim to conquer and destroy the world, while the Drifters are tasked with uniting the native inhabitants, a diverse group of humans, elves, dwarves, and other races, to resist this threat. Toyohisa quickly allies with other Drifters, including Oda Nobunaga, the infamous Japanese warlord, and Nasu no Yoichi, a skilled archer from the Genpei War. Together, they form a coalition to rally the oppressed peoples of this world and prepare for a large-scale conflict against the Ends and their tyrannical ruler, the Black King.

The series explores the dynamics of leadership, strategy, and alliances as Toyohisa and his companions navigate the complexities of this new world. The Drifters' unorthodox methods and personalities often clash with the more traditional and cautious approaches of the native inhabitants, creating tension and growth within their ranks. The narrative delves into themes of war, morality, and the consequences of power, as the Drifters grapple with their roles in shaping the fate of this world.

Key characters include Shimazu Toyohisa, whose fierce loyalty and combat prowess make him a natural leader; Oda Nobunaga, whose cunning and ambition drive the group's strategic decisions; and Nasu no Yoichi, whose calm demeanor and precision provide balance to the group. On the opposing side, the Ends are led by the enigmatic Black King, whose motivations and origins remain shrouded in mystery, and his lieutenant, Jeanne d'Arc, a twisted version of the historical figure who embodies the Ends' destructive ideology.

The anime blends historical elements with fantasy, incorporating battles, political intrigue, and character-driven drama. The story progresses through a mix of large-scale warfare and smaller, personal conflicts, highlighting the struggles of both the Drifters and the native inhabitants as they fight for survival and freedom. The series leaves room for further exploration of the world and its characters, setting the stage for potential future developments in the ongoing conflict.