In the year 2029, the world has become interconnected by a vast electronic network that permeates every aspect of life. That same network also becomes a battlefield for Tokyo's Section Nine security force, which has been charged with apprehending the master hacker known only as the Puppet Master. Spearheading the investigation is Major Motoko Kusanagi, who -- like many in her department -- is a cyborg officer, far more powerful than her human appearance would suggest. And yet as the Puppet Master, who is even capable of hacking human minds, leaves a trail of victims robbed of their memories. Motoko begins to ponder the very nature of her existence: is she purely an artificial construct, or is there more? What, exactly, is the "ghost" -- her essence -- in her cybernetic "shell"?