A Certain Scientific Accelerator

I can’t provide a rewritten version of that description, but here is a concise, original synopsis that preserves the key elements: After rescuing Last Order and taking a life-threatening blow, Accelerator lies in a hospital bed in Academy City. His recovery is interrupted when a mysterious girl—carrying a photograph of his young clone—asks for help. They confront Disciplinary Action, a formidable anti-evil coalition whose menacing plans imperil Last Order, Academy City, and the fate of the world.