The TARDIS: a powerful time travel machine, bearing at her heart the Vortex. Under the guidance of the somewhat fey Time Lord known as the Doctor, she travelled the universe literally from one end to the other. She had gone back and forth, round and round, and sometimes inside-out and around herself. There were very few other TARDISes travelling in the universe: very few. The Time Lords were a sombre and retiring species, always preferring to watch rather than act. The Doctor was strange, a bit wild, and determined to make a difference, to end injustice, to give everyone he met a chance at a better life. And the TARDIS loved him for it.
She loved him as an old man, and as a young one. No matter how he changed, she knew him. He was the Doctor. He was the centre of her existence, the focus of her reality. Only a madman would dream of attempting to change the bond between them. Only a genius would have a chance of succeeding.
Someone who was both was going to try.
* * *
The seduction had begun quite innocuously, to the uninformed eye. On a planet named Skaro, the Doctor had held the door of the TARDIS open for a few moments longer than was strictly necessary (distracted, reasonably enough, by someone holding a gun to the head of his companion Romana). Those moments were all that was needed.
Five tiny silver ball bearings had neatly popped through the TARDIS door, and promptly rolled out of sight in wall seams, in the control console, or scooting away down the corridors. One of them had slid inside the casing of the robot the Doctor called K-9 Mark II, and vanished from detection. They concealed themselves, and they waited. The Doctor and his companion left Skaro, unaware of their extra passengers.
The TARDIS did not know what to make of these intruders at first. The Doctor had dragged all manner of flotsam into the TARDIS over time: humanoids, sentient plants, garrulous pieces of stone, clothing of every description, toys and instruments and furniture, souvenirs from a thousand places and times. These bearings had come in under their own power, true, but now they just sat where they had hidden, and did nothing. They drew no power, interfered with none of the TARDIS' circuitry or fields, and emitted no energies. K-9 did not appear to be affected either. The bearings just sat there. Waiting.
For years they sat there, while the Doctor and his TARDIS travelled and explored the universe. The TARDIS was always aware of them, as she was aware of millions of things at once. But apparently they were completely inert.
In reality each of those tiny silver spheres was packed with atomic-level circuitry. They had been created by quite possibly the greatest scientific mind in the universe. The bearings were constantly in contact with one another, iterating and debating their future actions. But they were not here to destroy. That was not what their maker had created them for. They were watching, and they were waiting. Waiting for something to happen.
It was a great rift in the fabric of Time, and the Doctor piloted just a bit too close to it. In an instant, the rift's energies took the TARDIS and shook her like a leaf in a hurricane. She strained, fighting back not just under the commands sent to her by the Doctor, but also using her own powers, making her own decisions. She bent and whirled and side-slipped, and soon was sailing smoothly through the time streams.
"Well done, old girl," said the Doctor, patting the console. And inside the console, one of those tiny ball bearings broadcast an agreement, on a frequency where only the TARDIS would detect the message.
"Well done, TARDIS!"
* * *
That was how it began.
The bearings were no longer inert: occasionally they issued praise to the TARDIS, always addressing her directly and not the Doctor. Sometimes their praise was words, sometimes song, sometimes feelings. They seemed to be making no other actions, so the TARDIS did nothing but watch the eight of them.
The TARDIS went back through her memories, and discovered that at some point, the four ball bearings she could detect had become six, and now eight. Were they absorbing her material, eating her?
But no: she saw them in her memories, merging with dust and tiny bits of scrap metal, slowly growing in size and then dividing. Now her attention focused on them, painfully intense, sharp as needles and cold as space, striving to penetrate their plain silvery exteriors and determine exactly what they were doing.
It seemed that they felt the weight of her regard. Slowly, laboriously, they moved and crept towards one another. Where there had been eight, now there were seven - then six - then four. The original four went back to their nooks and crannies as though chastised. And the TARDIS turned her attentions elsewhere. She did not realise that though the eight ball bearings were now four, they still had the mass of eight - and she did not know that with extra mass came extra computational ability, as they converted themselves into pure circuitry.
* * *
More years passed, and the TARDIS still thought about her guests. First they had been flotsam, then intruders: she was never quite sure when they had become guests. They sat and they offered praise on occasion, and that seemed to be all. They didn't seem to be paying any other attention.
She wanted attention, though. Or acknowledgement at least. Didn't these things realise that they were inside a time travel machine of superb delicacy and skill, that could choose which side of an atom to land on, that had faced horrors and glories unimaginable and come out through the other side without so much as breaking a teacup in her cupboards? That she had seen the Universe from its fiery beginning to the dark and dusty end, that nothing was barred to her?
The bearings maintained their polite distance.
Then disaster. A systems failure, sparking chain after chain of interlinking collapses after the first crucial link snapped. Centuries of repair on repair, of odd jury-rigged replacements, had finally weakened one too many critical functions. The TARDIS fought, and the Doctor fought along with her, to hold back the energies inside and out that could tear the timeship into shards of space-blown metal. They both fought, but they were losing. The TARDIS reached out, strove for more control, more power - and found it.
The bearings offered her themselves, and she accepted them. Together they juggled ten thousand formulae, diverted power through countless circuits, shunted and inverted and grounded and rerouted. As though from the centre of time, she saw all of herself at once, and knew just what to do to slow and contain the runaway energies, stop the failures.
Together, they saved themselves. They saved the TARDIS.
And while the Doctor spoke words of unheard praise and dove under the console to try and figure out what had happened, the TARDIS focused again on her guests. Now, she thought. Now they will use the power I have given them, reach through the channels I have opened to them. Now they will attack, now they will reveal their true purpose!
But they didn't. Carefully, politely, they withdrew from contact with her circuits, with a finicky nicety. Making sure that not a single atom of their substance was left entangled in her relays and wires. And then they sat again, inert.
How easy it would have been, right then, to signal the Doctor that something was wrong! From where he lay, he need only examine the panel by his left ear to see the tiny bearing sitting at the seam, like a leftover bit of solder where no solder should be. One alarm, one stuttering wire, and the secret would be revealed. The Doctor would scrape the bearings out of the TARDIS and nullify them. Get rid of them.
She didn't want to be rid of them, though. She wanted to understand them, find out why they had come here. And somehow she could sense that they desired to understand her as well - and that desire was not unwelcome to her.
* * *
The K-9 unit was gone, and one of the bearings with it. That was the way things were. People came, people went. Only the Doctor was forever; only the Doctor and the TARDIS.
Now and then a bearing would roll out the door after the TARDIS had materialised, but it always came back before she left. Or at least, a bearing identical in every way and measure to the one that had left came back.
The Doctor changed. Regeneration: and it was as frightening to the TARDIS as feeling her own heart being taken out by invisible hands, rotated and twisted in some indescribable fashion, and then returned to her. He did return. Changed, a new face and body, exchanging scarf for celery, but the soul inside was unchanged. He was still her Doctor. She was still his TARDIS.
She changed as well. When she was frightened, the bearings comforted her: when she was wounded, they helped her maintain cohesion, showed her the way to heal. Slowly, over thousands of days and hundreds of thousands of communications, the guests became friends. The TARDIS' friends, not the Doctor's. They were here for her. They spoke to her. And sometimes when they thought and she replied, it was as though two halves of the same mind were speaking, they had grown so close. She knew them so very well, almost as well as they knew her.
Now was a time when their thoughts were almost one.
~We see a thing, in a future,~ they thought, and in their mutual mind's eye they both looked on a great black hole in the fabric of the Vortex, where Gallifrey itself would be destroyed.
~It has happened. It will happen,~ thought the TARDIS, and her thought was deep with that terrible knowledge.
~It will hurt the Doctor. It will hurt him terribly. It will drive him to do the thing that should not be done.~
The TARDIS waited for the silver bearings to go on. Eventually they did.
~He will try to change his own past. He will make a contract, try and change a crucial point in his own history.~ The bearings paused again. ~And he will succeed.~
The TARDIS gazed into her own heart, and saw bright rippling lines of change lapping around the black hole where Gallifrey had been. And inside that hole something was lurking: a bright shadow, a silent promise. Of a Gallifrey that could be more than it had even been.
~We are a part of the Doctor's contract,~ thought the bearings. ~We were sent to you. We have a plan that will change Gallifrey. That will prevent it ever being destroyed. So that the Doctor will be safe. But we need your help.~
And then they waited…and waited. Waited for the TARDIS' answer.
It came in a flame of emotions, in a wall of calculations, in a shuddering at the heart of the Vortex.
And the universe changed.
Notes on the Tale:
The bearings were invented by Davros, creator of the Daleks, and deployed in my story 'Doctor Who and the Enmity of the Daleks.' The results of their deployment is seen in the sequel, 'Doctor Who and the Exodus of the Daleks.'