"The Seven Deadly Sins: Four Knights of the Apocalypse" is a sequel to the popular manga series "The Seven Deadly Sins," created by Nakaba Suzuki. The story is set several years after the events of the original series and introduces a new protagonist, Percival, a young boy raised in isolation on God's Finger, a remote and mountainous region. Percival's life takes a dramatic turn when his grandfather, Varghese, is attacked by a mysterious knight named Ironside, who claims to be Percival's father. Varghese sacrifices himself to save Percival, urging him to flee and seek out the truth about his lineage and destiny.

Percival embarks on a journey to find Ironside and uncover the secrets of his past. Along the way, he encounters a diverse group of allies, including Donny, a skilled archer, and Nasiens, a mysterious alchemist with a hidden agenda. Together, they face numerous challenges and adversaries, gradually uncovering the existence of the Four Knights of the Apocalypse, a prophesied group destined to bring about the world's destruction. Percival learns that he is one of these knights, and his journey becomes intertwined with the fate of the world.

The narrative explores themes of destiny, identity, and the struggle between good and evil. As Percival and his companions travel across the land, they encounter remnants of the Holy Knights and other factions vying for power in the aftermath of the original series' events. The story delves into the complexities of Percival's heritage, revealing connections to the Arthurian legend and the broader mythology of the series' universe. The characters' growth and relationships are central to the plot, with each member of the group contributing unique skills and perspectives to their shared mission.

The manga maintains a balance of action, mystery, and character development, with a focus on Percival's journey of self-discovery and his role in the unfolding prophecy. The world-building expands on the established lore of "The Seven Deadly Sins," introducing new locations, cultures, and conflicts while maintaining continuity with the original series. The narrative builds toward a larger confrontation, as the Four Knights of the Apocalypse are drawn together by fate, setting the stage for a climactic battle that will determine the future of their world.