With Major Motoko Kusanagi missing, Section 9's Batou is assigned to investigate a string of gruesome murders—seemingly at the hands of faulty gynoids, or sex robots. But when a faulty gynoid leaves Batou a cryptic message, he begins to question the cause of their malfunctions. Suspicions of politically motivated murder and an illegal "ghost" quickly crop up, drawing Batou and his partner Togusa into a perilous web of conspiracy.

As their investigation goes on, the line between man and machine continues to blur, and reality and perception become indistinguishable. Confronting strange and dangerous foes, Batou and Togusa explore a futuristic world filled with machines and living dolls but utterly devoid of humanity.