Japanese animated films and anime series are weird. But the release of the classic Ghost in the Shell over 20 years ago drove the genre both upwards by reaching adults, and outwards, reaching the West’s mainstream unlike other previous efforts. It did this while blending sci-fi elements, cyberpunk visuals and deals explicitly with mature themes and ideas.

The film starts with a mysterious woman removing wires from the back of her head as she observes buildings and traffic from dizzying heights. She soon descends into a building by crashing through the window, killing a high-level diplomat and escaping right in front of everyone else using some nifty high-tech camouflage.

The story follows Section 9, a public security agency headed by Motoko Kusanagi, tasked with finding an elusive uber-hacker known only as the Puppet Master. This mysterious criminal is able to hack into the bodies of others, effectively rendering them simply as shells (hence the title) in order to alter the memories and conscious state of their minds.

This high-concept plot results in a journey untangling a web of political corruption and cover-ups, finding out what's behind the Puppet Master's actions and its ultimate motivations.

Given the major current interest in the science of ageing and "internet of things", this film couldn't be more relevant. In fact, Kusanagi has an interesting monologue early in the film, where she discusses how her world was only dreamt of as science fiction not so long ago, where a body's metabolism and biological processes still matter, but they can be separated from someone's thoughts and memories. We should remember that the film takes place in 2029.

Kusanagi also questions what her existence means or even is, and whether she is just a synthetic being created by scientists, with neurological implants aimed at making her more productive. She asks her colleague Batou, "I mean who knows what's inside our heads. Have you ever seen your own brain?" and examines whether a hyper-connected cyborg could create its own soul all by itself? This scene ultimately poses the final scary question: what is the purpose of being human?

As you've probably gathered by now, the story deals with concepts of identity, the ubiquity of technology and its uses, and the political and societal implications of a technologically advanced society.

The presence of naked female shells is fascinating. Yes, the female body and female characters are already disrespected in films, games and you know, life in general. But don't mistake why such visuals are used in the early scenes in this film: after asking whether you think they're a necessary element, you're left asking by the end of the film what exactly are the uses of a human body which has no unique identity of its own.

For many, many years, philosophers and super-smart thinkers have asked the question what it actually means to be human, both literally and figuratively. Philosophers have been thinking about the “zombie” scenario: there could theoretically be two identical versions of a person, able to carry out actions in exactly the same way, but one might not show any signs of consciousness. The doppelgangers are just replicas. This film asks what it means to be conscious and whether an identity of ours exists outside the immediate physical realm.

Although there are frantic technological advances in many frames throughout the film, some things remain the same, such as scheduled household waste collection and people shopping in stores (sorry, Amazon). Nonetheless, the visuals are quite simply vivid and memorable, especially when no other film, animated or otherwise, comes close to making humans feel so small, questioning our role in a world filled with technology, and a lack of an accompanying “moral compass 2.0”.

Ghost in the Shell was originally told through serialised Japanese manga in 1989, by the visionary Masamune Shirow. Numerous films, anime series and computer game adaptations have followed ever since. Hollywood will attempt a live-action adaptation starring Scarlett Johansson, scheduled for release next year. The production has been heavily criticised for whitewashing all of the main characters when the film industry is under fire for failing to allow black and minority ethnic talent to break through.

It makes the original film even more urgent viewing, especially with the rise of today’s artificial intelligence and what role humans will play in a future world where more tasks will be sufficiently carried out by robots.

This topic is mentioned in the film, as the Puppet Master quips bluntly about the dangers of depending on technology too much, and the threat of a virus being able to corrupt a whole set of interconnected systems. They go on to say copies aren't much use either, as they "do not give rise to variety and originality. Life perpetuates itself through diversity".

Perhaps Ghost is hiding a simple morality tale, warning us of the need to be more original. But we can only do that if we know what our unique identities are and the purpose of our existence. We'd better hurry up though. As the Puppet Master says, “the net is vast and infinite”, and we can’t lose ourselves inside a meaningless abyss.