In the aftermath of the Global Simultaneous Default and the rise of advanced artificial intelligence, the world is entrenched in the Sustainable War, a perpetual conflict. Public Security Section 9, headed by the cyborg Kusanagi Motoko, emerges to combat cyber threats from the enigmatic Posthumans. Amidst the ruins of Tokyo, they encounter the mysterious 'N' refugees and a hostile American Special Forces unit. As tensions escalate, the looming specter of nuclear devastation looms, sparking a treacherous three-way clash for supremacy.