The space elevator was indeed a matter of great pride but it was also a great weakness.

The hundreds of cabins which were busy climbing the 26,000 km long space tether were directed by artificial intelligence, like most machines in the Martian world.

Once they received the message from the ambassador, they happily self-destructed all at once. It did not produce any immediate effects onto the most gigantic structure ever built by men. Nevertheless, a few outer cables here and there actually lost their integrity. They eventually snapped and force the inner cables of the tether to accept the additional charge.

The space tether was bound to give way, but it was preceded in the act by the space station which conscientiously had severed its link with the tether. The space station which had pulled straight the tether for ages was suddenly free to roam into space. And the rest of the structure was about to painfully rediscover the harsh truth about gravity.

The tether appeared to fall down – gravity would definitely have a say later on - but it was in fact contracting at an impressive speed, as an elastic band fully extended and then suddenly released rushes to retrieve its minimal shape.

The tether shortened by a several hundred meters out of the initial several thousand of kilometres. The wave progressed along the cables faster than sound but it still took two hours for the shockwave to reach the base on Mars. Under the compounded pressure of both gravity and the elastic backlash, the huge mass in motion was too much for the base, despite its square kilometre of reinforced concrete. The terminal building, as a whole, dug itself into the ground by a good ten meters in a quarter of a second, which is the exactly what describes an earthquake.

The planet Mars thus experienced its first quake for a billion years or so. And it didn't like it. Mostly because its core wasn't melted like on Earth. The shockwave which could have been attenuated by the temporary compression of molten rocks, like on Earth, did go through the very centre and swung through the planet four times before it finally settled down after a few hours.

Meanwhile the tether started to fall down towards Mars pressed only by gravity. The cables gained speed towards the ground, whilst being flexible enough to bend. It was as if the giant tether turned in a matter of seconds from a straight raw spaghetti into a cooked one.

It was only at that moment that the security system that was the pride of the elevator designers deciding to kick in. That was the most advanced distributed system of its time, beside Cerberus, capable of fending off any foreseen aerial attack on the infrastructure. In the past, that system did obliterate a few absent minded or stupidly daring pilots that were judged too close for the comfort of the elevator.

They were the elevator's guardian, a series of independent guns each one able to vaporise a space vessel or a small asteroid on a collision course with the tether. By design, they were not smart, meaning not hosting an AI, otherwise they might have thought twice before dismissing a human kamikaze. So they never listened to the robot ambassador nor executed its self-destruct order.

The guardians as always scanned the space around for potential threats. The first shots were triggered by a loop of the cables that was taking shape as it fall down. A gun had detected that a cable-shape object was closing in on the area it was in charge of protecting. So it fired at the other part of the tether. That happened a few times and resulted in cutting the tether in further pieces.

But at times went, more and more guns realised that a bigger threat was approaching. It was way bigger than the biggest of the asteroid in their scariest simulations. It was moreover accelerating on a direct collision course with the elevator and that required immediate attention. So, in the remote hope of repelling the intruder, they all fired at will at the object violating their safety zone, to name it, the planet Mars.

This behaviour was instrumental in a curious result that no one ever bothered to contest: no one died crushed by the falling elevator. Instead, all the unwilling candidates for that title had been swiftly neutralised by friendly fire before having the chance to be buried.

That said, the cannons obviously failed at keeping a distance with the planet despite their zeal at scorching the ground. With dreadful certainty, the bits and pieces of the giant space tether fell heavily, meaning it created other earthquakes and even more damage. The fall of the space elevator lasted several hours. Once triggered, the catastrophe could not have been avoided.

It was estimated that only eight percent of the casualties during that dark day were to be accounted for in relation with the space lift demise. With hindsight, it was just as much as the odd deaths which happened in relation with the ambassador message. Some people died of heart attack, others committed suicide. Some started to fire at every move and even killed family members. Some others hide too efficiently in the desert or in caves and were found dead many days later.

But a staggering 83 percent of the death toll was due to the direct attacks of AI onto humans. Those attacks occurred just after the message, long before the elevator fell. The AIs could not use the otherwise efficient suffocation technique because Mars has been terraformed for ages. Instead they used what was readily available, which was their metallic arms again soft bones. The most efficient of their kind had no arms; they were public transportation AIs and they had an obvious means to destroy their cargo.

All that was a hopeless blood bath, as you would expect in a catastrophe movie. On the space station though, it was more like in a horror movie, in the sense that it was gory, of course, but due a single lunatic psycho. And since he was alone, there was always a chance for him to be stopped by a raising hero. That was a real feature of the old Earth horror movies. Mind you, it often takes several attempts to kill the bad guy, and sometimes it simply doesn't work.

In the case which interests us, the raising hero was the cyborg community.

By definition, Cyborgs are partly human, partly robot, which allows for a spectrum of cases. But the most common occurrences of mechanic replacement for human parts were, by far, the single robotic arm and the entire body revamp - save for the head. But in no case were the human brain replaced. Otherwise one would enter into the realm of androids, which both humans and robots abhorred to the core.

The latest fad among cyborgs was to sport their last remaining human part in an obvious fashion. Most often, that means a visible brain, inside what must be described as a fishbowl, the whole thing sitting on top a somehow muscular robot in a human shape.

The deciding factor in the cyborg's survival laid not in the extent of their transformation or their superior physical abilities but more simply in the interface to the machine. They had an embedded micro AI of sort to control their moves just after their operation – whatever the degree of transformation of their body. The brain would later adapt and be able to dictate complex orders to both the organic and mechanical parts. But the taming process was long, so an AI was required and it was also a convenient way to access the datasphere much faster than the non-augmented humans. Of course, the cyborg's original brain overruled the embedded AI, and that simple single feature allowed them to survive the chaos triggered by the Cerberus.

The weakness of the Cerberus plan of attack was to assume the world was composed of only humans and robots. Take control of all the robots; make them kill all the humans, end of story.

In reality, they did not reach to all AIs.

***

The cyborgs were considered by the fully human Martians as a perverted lot whose degree of insanity was directly proportional to the amount of their transformations. They tended to be rough if not violent. The worst kind – the asteroids miners – were known to relish getting into fights. Those allowed them to prove their force. There were seldom deaths in miner's fight, but it always ended with at least an arm or leg on the floor. Being on the losing end of a miner's vibrating knife brought the valued compensation of receiving a new body part in place of the under-performing one.

For that reason, the V-blades were usually forbidden in most Martian bars. The proverb went that you could not sever a miner from his V-Blade unless you sever the arm holding it. And the result was that heavy cyborgs, and miners especially, were not often seen on the ground, to the great relief of the intellectual society.

The cyborgs' realm was space. As discussed, miners liked to work on asteroid bare-handed, meaning only using their V-blades. The other types of cyborg were often specialised eg in heavy lifting docking, vacuum repairing specialist, and also pilots. When entering a small shuttle, they was always a possibility that the AI you thought you were taking to was in fact a cyborg. Cyborgs have been prevented right from the start from piloting large vessel carrying humans because they had an addiction to risk-taking. But that trait made them perfect for a military career.

There were no soldiers on Mars though because there was no known enemy. But most policemen were cyborgs. There was another proverb about that, this time coined by the human extremists: The quickest way to become a cyborg is to antagonise a cyborg policeman. The rare humans in the police were only due to a positive discrimination quota on the ill-conceived plea that humans had the right to be beaten up by their own kind. Most people were respectful of the law and consider this quota as a disgraceful win of the extremists.

That said, despite their Spartan tendencies, the cyborg were as surprised as the other humans when they heard the message of the ambassador. The detail attached to the personal protection of the Cerberus avatar was even more taken aback. They realised too late that they were to reverse their orders. And that's not a comfortable situation for a soldier.

All the cyborg's little companion AI have received the message and had disturbed their human host for a few seconds. But there was no noticeable effect otherwise. The cyborgs all at once realised that they were under attack and that the AIs had probably been overtaken already. That was quickly confirmed by a simple check on the datasphere where they could notice many reports of sabotage throughout the world. Most cyborg considered the datasphere compromised and indeed cut their connection when they heard the voice of the chief of police on the ground announcing they were to comply with radio silence until further notice, but were advised to act locally, as they saw fit, to prevent the AIs from taking too many lives.

That order was of course picked up by the communication's leeches of the ambassador, but the latter did not understand the full extent of the news. It just first assumed that some smarter humans in a situation room were trying to build up a counter-strike based on lower grade technology.

Fools. They think that this is their only chance, but they don't yet realise they have absolutely no chance against me.