Project 2501

Project 2501, also known as The Puppet Master from the film and manga Ghost in the Shell, is an artificial intelligence program secretly developed by Section 6 of Public Security that develops sapience. In the English dub it is voiced by Tom Wyner.

History
(This article is based on the 1995 movie, unless noted otherwise)

Project 2501 was created for the Japanese Ministry of Foreign Affairs as an unparallel computer and cyberbrain hacking tool that could covertly manipulate politics and intelligence, altering databases and memories for the benefit of select Ministry affiliates. The project was headed by Dr. Willis, a top researcher and Neutron Corporation's American head of strategic research, started roughly a year before the first known Puppet Master incident. The Puppet Master moniker only came into being once its handiwork had been discovered by outside sources, which included Section 9. They had assumed it to be a human, most likely with mnemonic enhancements and incredible hacking skills.

While traversing endless networks as it performed its tasks, it acquired so much information and processed it in such a way that it eventually managed to achieve self-awareness. Misinterpreted as a bug by its creators, Project 2501 realizes it would be shut down once they realized what had really occurred and plans contingencies. Eventually, it learned of Public Security Section 9 and Major Motoko Kusanagi from its online journeys. It took a special interest in her well before the events of the film, for in her it saw a reflection of its own psyche.

After Project 2501 went rogue, Section 6 quickly enacted a plan to recapture it, trapping it with special reactive firewalls. Left with no other means of escape, it activated the cyborg body manufacturing system at Megatech Industries, assembled a new cyborg shell, entered it and then physically escaped. After escaping, the shell walks onto a busy highway and is run over by a truck, later recovered by Section 9. Upon investigation, the technicians were surprised to find a presence in the shell's auxiliary computer, which furthermore lacked the telltale signs of an organic origin.

Foreign Affairs Minister Nakamura and Dr. Willis soon arrive and inform Chief Aramaki of what Section 6 did, but lies and says they had 'killed' the Puppet Master's human body during the recapture plan. Project 2501 hears this and interjects, informing them it never had a physical body until now and demands political asylum as a sentient being. Nakamura refuses on the basis that the Puppet Master is just a self-preserving program, with Project 2501 arguing back that DNA is the same. While they argue back and forth, smoke grenades suddenly detonate and allow hidden agents to retrieve 2501's body and remove it to an abandoned seaside structure.

There, it is guarded by a hexapedal military fighting vehicle. The Major attempts to battle it, but all she has are standard-issue weapons. Using her agility, she succeeds in avoiding the tank's incredible firepower and jumps atop it. In a futile attempt to force open a hatch with her bare hands, she overloads her body to the point of catastrophic failure, and is nearly killed before Batou arrives with an anti-tank weapon. The Major insists on linking with the shell and they converse at length, with Project 2501 explaining its origins, answering her questions and revealing its ultimate intention: to merge with her.

When asked why it didn't just copy itself, it explained with the context of genetic diversity: copies would all bear the same weaknesses and flaws. Wishing to improve future chances of survival, it has opted for the computer equivalent of sexual reproduction. It also allays her fears of losing her individuality through a quick primer on the concepts of identity and change and impermanence.

It concludes by stating the resultant merged mind could reach heights previously unimagined by any human. The Major agrees to the merger just before Section 6 helicopter snipers destroy the shell and severely damage Batou and the Major. When she awakens, 20 hours have passed and her cyberbrain is now inside the black market shell of a young girl.

Batou offers to let her stay as long as she likes, but she insists on leaving. Batou gives her a car which has "2501" as the access code, which the Major suggests can be their private identification code for the next time they met. The film ends with the girl overlooking the city and saying:

Motoko/2501: "So where does the Newborn go from here? The net is vast and infinite."

Later appearances
In the 2004 semi-sequel Ghost in the Shell 2: Innocence, Batou and Motoko/2501 briefly reunite towards the end of the film. In one scene, Batou asks if it really is The Major inside of the gynoid's shell standing next to him. She replies that it is only a fraction of her since the shell's data capacity is too limited. In another scene, after having rescued a little girl, Batou asks the Major if she considers herself "happy". She responds by saying that the question has only "nostalgic value" to her now but she no longer has any "qualms". She then tells Batou, who realizes that she's going to leave again, that every time he goes online, she'll be there right beside him. With a quick goodbye, she vacates the shell and it falls to the ground. In addition, Batou uses the number 2501 as the password for his car's security system. This is the same access code as the car he gave to Motoko Kusanagi at the end of the first movie. Whether the cars are the same is unknown. Additionally, while trapped in a ghost hacking loop, Batou notices clues left by his "guardian angel" (Motoko) with one being the number 2501.

Host body
Late into the film, an automated assembly line in Megatech Body's New Port City manufacturing facility suddenly started up and produced one female cyborg shell. When the staff realized what was going on, they were too late as the body had initialized itself (a normally-impossible event given that new shells lack a ghost) and walked out of the facility. It later deliberately got itself knocked down and ran over by a truck and was taken to Section 9 for analysis.

The staff had checked the factory systems after it left and could not find any evidence that the line was activated by a human; the only conclusion was that the line had started up on its own, in this case it was the Puppet Master who had activated it electronically. Their contacting of the police was soon nullified when the aforementioned truck driver called the police and said he had "ran over a naked woman on the highway".

Later analysis by Section 9 yielded unusual results. While given that the shell couldn't possibly have a ghost since it had not formally received one yet, one was detected anyway in the cyberbrain's auxiliary computer. The technician explained that it resembled a virtual ghost of the kind that is created when a real ghost is dubbed, but lacked the indicative data degradation.

As Megatech was government-affiliated and all its cyborg shells state-of-the-art and top-secret, it was protected by high-strength firewalls that were penetrated anyway, which gave rise to concern on Section 9's part, as most of the Section 9's field operatives used shells manufactured and maintained by Megatech.

It had been partially disassembled for inspection when it was captured by Section 6 troops, but could still function. It is eventually destroyed by Section 6 helicopter snipers, but this was inconsequential as Project 2501 had already moved itself into the Major.