He couldn't have been unconscious for more than a few seconds, but when he came to, everything had changed.

He was lying on his back, arms crossed over his head and eyes, still in the act of protecting himself from the thing that had been charging towards him across the common. The explosion that had knocked him out had also left his ears ringing, and the world around him had become a dull, distant presence with a feeling of unreality about it. He opened his eyes and cautiously looked around him, confused thoughts about what had happened to cause such an explosion running through his mind. An after image formed by the blinding light that accompanied the bang was still there, a vertical line of ghostly green that remained wherever he looked, and he blinked several times trying to clear it.

A few feet away lay the head of the chimerical dog, smoke drifting lazily upwards from one eye socket, and beyond it, no more than a stone's throw away, was a small crater around which lay numerous smouldering remains of the device. He looked up and about him for signs of the bird of prey, but he couldn't see anything against the blackness of the star-strewn sky. The only movement in the heavens was a bright point of light travelling towards the south-east, which Farron recognised as the Sentry - a still-orbiting piece of space hardware left over from the last age that had been a familiar sight over the Protectorate on clear nights. Odd, that it should be there now, just after the explosion. He watched it for another minute, until it moved out of sight below the horizon, half formed suspicions gathering at the back of his mind.

Farron rolled onto his side and grunted as something sharp jabbed into his ribs. Feeling under his cloak he found that he had been lying on the crossbow Peter had given him. Kneeling up, Farron quickly looked over the device hoping he could use it should any more false knights turn up, but his efforts at working out the weapon were frustrated by the darkness and his lack of knowledge. The best he might be able to do should one turn up was hit them over the head with it.

The sound of wings in the darkness made him pause and look around. It seemed unnaturally quiet now after the turmoil of running and shouting that had preceded the explosion, but somewhere to the south was the distant clatter of a running horse, getting quieter all the time. Even as he listened the noise faded away completely and he was left alone with only the sound of the soft swish-swish of a large bird circling him out of sight. 

-Are you hurt? Can you move?

"Yes. Who are you?" asked Farron, uncertain whether he should trust the voice in his head.

-I'll explain later. For now, I just need to get you moving. There may be more coming and your chances at escaping again are very slim.

"You're a chimera, aren't you?" Farron stood and flexed his legs while checking himself over for any injuries from the blast that he hadn't yet noticed. "I thought they were all gone."

-And yet, you met two tonight. One of which would have probably killed you, while the other, myself, belongs to you and aims to keep you safe.

"You belong to me! What does that mean?"

-I am yours, since you activated the key which binds me to you. Until you die, my purpose is to serve and guide you. Hold out your left arm, Farron, and brace yourself.

Farron did as he was told, and a second later the bird of prey landed gracefully onto his outstretched forearm. Even in the darkness, Farron recognised it as a buzzard, a common bird in the Protectorate, often seen circling over the fields and heathland. It held itself unnaturally still and regarded Farron with an intense gaze that unsettled him, as if the thing was considering whether to strike at him with its sharp beak.

-Do you understand what is happening here, Farron? 

"No, not really. These people want me for some reason. I don't know if they want to kidnap me or kill me, but they seem determined. Can you tell me what's going on?"

The bird considered Farron for a moment before answering, and when it did it sounded less certain. 

-Not everything, no. I operate under certain restrictions that limit my capacity to remember. However, I am certain to know more than you do and can tell you what I know, so that you may stand a chance of surviving, for it is very important that you do survive, Farron. A lot depends on it.

Farron shook his head and tried to gather the storm of questions forming in his mind. So much was happening it was hard to know where to start. 

"So, you are bound to me, by the key given to me by my father. You are the thing he left me, yes?"

-Yes.

"And you are obviously some kind of chimera, which is impossible."

-Yes. We should start moving, by the way. And you don't need to talk out loud, just think the words you wish me to hear, and I will hear them.

"How is that possible? It happened before - I don't understand."

-I cannot explain it now. Just accept that you can do it where I am concerned. Head south, we need to get to the bridge by daybreak.

At this, the bird took off and was immediately lost in the darkness. Farron shook his head in disbelief, then set off down the slope which lead to the fields and floodplains bordering the estuary.

"Are you still there?" he asked in his head.

-Yes. I am two hundred feet above you. I will continue to climb to one thousand, then circle around you at a radius of one kilometer to look for danger. We can communicate at all times.

"What exactly are you, and do you have a name?"

-I am a bird-of-prey chimerical, point-eight AI score, manufactured at the SimCore Industries facility at Mountain View, Colorado. I was initiated on 21st July 2718 and assigned to SimCore special projects under the command of Hallem Loveridge, the man you knew as Sable Holm. He gave me the name Zephyrus.

What the chimera - Zephyrus - was saying didn't make any sense. Farron knew that the last chimeras had been made at the end of the technological age, more than three hundred years ago. It was not possible that a device such as Zephyrus could have been made less than twenty years before now, and Farron said so, unable to accept the implications of what he was being told. 

-I can assure you that is correct, said Zephyrus. There is certain information I can still recall from the time I was brought into being. My time of creation, I am certain of, to the nearest millisecond.

"So", thought Farron, "You know how old you are. But you said you had 'certain restrictions'. What are those?"

-My memory is limited to a rolling five-year timescale. That is an unavoidable consequence of being physically small. In any case, a chimera such as myself would not be expected to survive more than a few years in normal service. Enough talk now, you are still in danger and there is a long way to go before dawn. Concentrate on getting to the southernmost bridge, there will be time for talking later.

Farron wanted very much to ask more questions, but the tone the bird had used suggested they would not be welcome just now. Instead he set his mind on walking, taking the most direct route he could towards the southernmost bridge - the one that could still be crossed - for he assumed that Zephyrus wanted him to do exactly that. The prospect of crossing it caused him some anxiety. Already he was further away from home than he had ever been, and he had heard rumours of the wild nature of the country across the water from the Protectorate.

The land began to flatten out as he approached the marshes. Ahead of him the lone tower of the northern bridge pointed skyward like a finger pointing to the heavens. Shapes and half seen movement made him jump every now and then, but nothing more innocuous than a disinterested pony and the occasional deer could be seen in the darkness. An hour later, Farron had begun the climb over a low hill from which the northern bridge had once began its crossing. Shortly afterwards the southern bridge came into view, its winding route across the estuary showing as a ghostly whiteness against the black waters.

Stopping for a drink from his flask and a piece of stale bread, Farron felt it was time to ask Zephyrus why she wanted him to cross over the estuary, explaining his reasons for heading to the Atlantic ports.

-Going to the Atlantic ports would be a waste of time. Your way lies west. There is something held near the fortress at Pembroke that you need to retrieve. This is necessary, Farron, trust me in this.

"For what purpose? Why do I need to do this? Sable didn't tell me much, and I'm being hunted for something I don't understand! Now you're telling me to go to some fortress across a hostile land where anyone who sees me is likely to try and kill me! You need to tell me why, or am I going to be left in the dark again?" His frustration at the lack of information being given to him was building up intolerably. He felt abandoned to circumstances beyond his ability to control without any explanation, and he wanted to know now what was being asked of him before he continued. If Zephyrus couldn't do it, or refused, he would ignore her and carry on south as he had planned, and try to meet up again with Peter and the Godwits, who he hoped had escaped safely from the ambush. 

Shouldering his backpack, he set off, telling Zephyrus of his decision as he did so. They argued back and forth for some time with Zephyrus becoming more and more agitated and cross. Eventually, as Farron took a path that led away from the bridge and on to the south, Zephyrus came back to him, barreling out of the darkness at high speed, wind rushing over her wings from directly in front. Farron ducked as she streaked past his head, but not enough to avoid getting a sharp tap from a wingtip.

-Obstinate boy! yelled Zephyrus as she circled back around and landed in front of him, ruffling her wings and doing a good job of appearing genuinely cross. 

"I'm obstinate! I'm the one being kept in the dark here! Just you tell me why you want me to do what you say! Until you tell me what's going on, I will not cross that bridge!" Farron was shouting out loud, pointing towards the old bridge that lay a mile or so to his right. The first signs of dawn were beginning to show in the east, and from where he stood, he could just make out the tops of the centre span towers, glowing against the darkness of the west. Zephyrus looked at him in silence for a few moments, then took off, circling higher into the sky until she was lost in the gloom. 

-Alright then. Obviously you have inherited Sable's intransigence. I will tell you what I know if you agree to walk towards the bridge. It will take some time, and day is fast approaching.

Somewhat appeased, Farron set off once more towards the bridge. Zephyrus flew on ahead a little to look for any trouble.

-I should tell you, Farron, that I do not know all the details. I can only relate what Sable shared with me over the last five years, and what I have deduced myself since. The rest is down to you. The first thing I can tell you, if you haven't already worked it out, is that you are not Sable's natural born son.

Farron paused in his step for a second, his breath catching in his throat. He had long suspected this to be so, but to hear it confirmed was a shock.

-Sable came to England alone, and sought you out once he arrived. He found you in a plague house near Plymouth, one of many abandoned children left on the door of the place, given to an order of new-life nuns who cared for those plague affected who were not found to be infectious. He then ... cured you. 

"He never told me how he did that. I assumed he had some kind of cure, but he never once to my knowledge attempted to cure anyone else who had been affected."

-I know. That's because he could only cure one person. Farron, I'm not sure now is the time to tell you how he cured you. You may find it disturbing.

"Stop putting me off. I want to know. I need to know!" 

-Hold out your arm, I'm coming back. Farron did as he was asked, and a few seconds later Zephyrus landed gracefully, folding her wings and giving Farron an intense stare. In the growing light it was possible to see her properly for the first time. It was slightly surreal to have such a powerful animal perched on his arm.  Sharp talons curled around his forearm and pressed gently into his skin. It took him a second to realise that Zephyrus was giving him a reassuring squeeze, and as she did so her head and body lowered slightly, so that Farron was left in no doubt that what she was about to say was something he would find hard to accept. Zephyrus was managing to convey a feeling of sympathy, just by the way she held herself. It was endearing and bizarre at the same time, yet it also sparked a feeling of companionship that Farron had been missing since his father's death. He couldn't help but smile, and nodded encouragingly for Zephyrus to go on.

-The red plague was - is - not quite what it seems. It is spread by a bacteria, but that is not what causes the plague itself. Indeed, the bacteria is actually harmless. Do you know what nanotechnology is? 

"Yes, I think. Sable mentioned it once or twice in my lessons. Small machines, so small you could fit thousands on the head of a pin."

-Then you may understand this. The red plague is not biological, it is mechanical. The machines are carried by the bacteria, and spread from person to person. Those that are susceptible to the bacteria will replicate enough to release a critical mass of nano-tech into their bloodstream. From that point, the tech goes to work. 

Farron's smile had faded, and his revulsion as to why anyone would want to do such a thing was written clearly across his face.

-It was not its purpose to turn people into mindless wraiths, Farron. It was meant to do something else entirely. But it didn't work. Either it was released by mistake, or through an act of war, or maybe by some malign person or government, but the point is it wasn't ready, and hadn't been perfected. What got released was a copy of another laboratory's tech, and as such it was poorly made. But once released, it spread like wildfire, across most of the entire globe within fifteen days and everywhere by six months. 

The point is this: you were infected by this tech. It's rare these days, as the original bacterium has mutated and become less virulent, but it does occasionally arise still. And you have it.

"But what was it meant to do? Why am I not affected, other than my red skin, if I have these machines in me?" 

-You were affected Farron, your brain was subverted by the tech when it replicated within you. Sable was able to restore you cognitive functions by injecting you with a form of the nano-tech that worked as it should have, repairing the damage and allowing your brain to function again. I'm afraid you were used as a test subject, Farron. 

"That makes no sense. Why not do that in a laboratory, if such a place still existed? Why come all the way here, and hide away in a Protectorate for so many years?"

-Because we are at war, Farron, and the prize is far greater than anything you could possibly imagine.  And as the only living proof-of-concept on this planet, you are valuable beyond compare, hence the need to hide you until the time is right.

Farron stopped and looked at Zephyrus, who's amber eyes found his own.

"What do you mean, 'proof of concept'? You make it sound like I'm some kind of machine." An uncomfortable feeling started to develop in the pit of his stomach, as realisation of what had happened to him began to crystallise in his mind. Zephyrus kept her eyes on his, but lowered herself further, before speaking.

-But that's exactly what you are, Farron. You do not have something that you would recognise as a brain inside your skull. You and I are kin. You are the first - and only - fully sentient human chimera on this planet. And there is something you must do, whether you want to or not.

Zephyrus took off once more, circling and climbing again into the pale blue dawn.

"What is it I must do?"

-That, said Zephyrus, is something I will tell you on the other side.