"Sentō Hakai Gakuen Dangerous" is set in a dystopian future where society is divided into factions ruled by powerful corporations. The story unfolds in a high school known as Dangerous Academy, an institution designed to train elite fighters who will serve the corporate overlords. The academy is a brutal environment where students are pitted against each other in deadly combat to prove their worth and secure their future. The narrative centers on a group of students who navigate this cutthroat system while uncovering the dark secrets behind the academy's existence.

The protagonist, Renji Kurosaki, is a transfer student with a mysterious past and exceptional combat skills. Renji quickly becomes a target for both students and faculty due to his refusal to conform to the academy's oppressive hierarchy. Alongside Renji is Aya Fujimiya, a skilled fighter with a strong sense of justice, and Tetsuya Shirogane, a former top-ranked student whose loyalty is tested as he grapples with the academy's corruption. Together, they form an uneasy alliance to challenge the system and expose the truth.

The plot delves into themes of power, rebellion, and survival as the students uncover the academy's true purpose: to create superhuman soldiers for the corporations' ongoing wars. The story escalates as Renji and his allies face increasingly dangerous opponents, including genetically enhanced students and rogue instructors. The narrative is driven by intense action sequences, strategic battles, and moral dilemmas as the characters confront the consequences of their choices.

As the story progresses, the group uncovers a conspiracy involving the academy's founder, who seeks to use the students as pawns in a larger scheme to dominate the world. The climax involves a high-stakes rebellion against the academy's leadership, with Renji and his allies risking everything to dismantle the system and free themselves from its control. The series balances its action-packed narrative with moments of character development, exploring the motivations and struggles of its central figures as they fight for their freedom and a chance to reshape their world.