After the Ood.

The more things change, the more they stay the same.

How many times had the Doctor seen proof of that simple sentence throughout his travels? And why was it the humans seemed to embody it throughout their long and sometimes really dismal history? For thousands of years the human race had constantly fought one another in bitter conflicts on Earth hoping to gain a bit more land or over some other silly dispute which in time would mean little one way or another later on, the Doctor had seen it so many times during his travels - he had dropped in on the Crusades and later on met gunslingers during his first incarnation, and the Jacobite rebellion in his second incarnation before going on to seeing the final days of the Selachian Empire before the humans used that gravity bomb on their homeworld. During that complex mess the War chief embroiled him in the final days of his second incarnation, the other Time Lord had told him that humans were a savage race, to which his second self had denied, but the other Time Lord had prepared his case and told him for half a million years humans had spent their time fighting one another.

The Doctor knew that the War Chief had told a basic truth. He more than most Time Lords had seen the best and the worst of the human race; one of the most memorable times he had seen them be amazing was during the Dalek invasion of Earth - in the primary timeline, not that unstable excuse that was created in the mess of Reginald Styles' failure to promote peace because humans couldn't really control themselves - and it was one of the few times he had seen humanity push aside their instability and work together as one people to overthrow the Dalek invasion.

But their darker nature came out more often than he would have liked; the Doctor had seen the human race conquer planets, build weapons to wage unnecessary and wasteful feuds when they could have used the same technical resources and intellect to build them in the first place to do something better instead, like that time he, Turlough and Tegan had been forced to land on Seabase 4 and encountered a paranoid future Earth to the one Tegan knew, and found Icthar and the Sea Devils planning to invade the base to fire its proton missiles to trigger the war to wipe out humanity to make it easier for the Silurians and the Sea Devils to retake the Earth.

Thinking of the Silurians and the Sea Devils made the Doctor grimace even more, and he was glad he was alone in the console room - Donna had left to head off to her room after their little trip to the Ood sphere, and though she didn't show it the Doctor knew she was shaken from what she'd seen; seeing her people do that to an innocent race…. While the Doctor enjoyed having her inside the TARDIS he did enjoy his own private time, and she seemed to have sensed he needed to be alone at the moment himself, and he was grateful to her for that - but he couldn't help it. The memory of being with Liz on Bessie when the explosives the Brigadier had planted inside the Silurian shelter colony near the Wenley moor research centre would still serve to anger him, and it had left a nasty legacy the Master had not hesitated to use against him during that mess with the Sea Devils. But looking back now after spending so much time fighting and losing so many of his morals along the way with the passing of his sixth life and entering his seventh and later lives and then fighting the Time War, the Doctor could see the logic behind the humans' actions towards the ancient species, making him realise his mistake in passing such a quick judgement.

The Silurians had not been innocent during that case; they had drained off the energy from the nuclear reactor from the research centre to revive others of their colony from hibernation - even now the Doctor was amazed still by the knowledge Earth hadn't always had its moon - and they were responsible for letting loose one of their resurrected dinosaurs which had been genetically reengineered to live in a world centuries beyond their original time, which had killed one of the scientists and had reduced another into a terrified state complete with racial memory that had left him in a catatonic state. It hadn't been until later the Doctor discovered that the Silurians had genetically engineered humans to provide a tasty food source which contributed to the racial memory, but he hadn't let that stop him from imagining humans and Silurians living in harmony together. It would have been the sign of intelligence if they both moved away from their differences, but they were both child races compared to the higher species out there in the universe.

When you looked at it from that perspective, it was no wonder his attempts to bring peace to both species ended up as a failure. One group was ruled by fear, the other ruled by prejudice. The good thing was certain members of the Silurian and Sea Devils were okay with the idea of making peace with humans and moving past the image they had of them as a primitive race rather than the evolved race they had become during the hibernation period, and even some humans had seen the potential benefits of peace, but the bad thing was the overwhelming hatred some possessed like the arrogantly hostile young Silurian, who had released that plague on the humans. After seeing so many people die from the terrible disease which the Doctor cured himself, could he say he had the right to judge humans for wanting to eliminate a dangerous threat?

No. And yet his third self had been angry, while deep down he knew that as far as how many shots were fired, the humans had comparatively done little towards the Silurians - Quinn may have imprisoned the one that idiot Baker had fired at and wounded when he'd cornered it in the caves, but that was one of a handful of disasters, and most of them were at the taloned hands of the Silurians themselves - the Brigadier may have planned to invade the cave network, but the Doctor knew that was because of his frustration at not finding anything concrete to explain the power failures at the research centre, no matter what Dr. Lawrence had thought.

The Doctor could understand now the logic behind the humans' actions which resulted in the destruction of the colony. It just did not mean he had to like it.

Genocide was one thing, something the Silurians and the Sea Devils weren't innocent of after their actions and threats towards humanity with their plague, their plan to destroy the Van Allen belt to kill humans by making them all die of sunburn on a cloudy day, and the Sea Devils desire to war which was encouraged by the Master, who only wanted the human race to die because of how he'd been caught and imprisoned, to that mess on Seabase 4 where they'd planned to triggering the war the humans on that base were prepared for, the war they'd practiced for but dreaded, but slavery was another thing.

The Doctor had encountered dozens of cases of slavery both on Earth and on other planets, and usually humans were at the centre of it, either the perpetrators or the ones enslaved by whoever was occupying their home planet or their colony world. He had met his friend Jamie McCrimmon during the Jacobite rebellion when a government appointed official had abused his position to sell Scots to the Caribbean as slaves on the plantations there, and he had left Susan during the end of the Dalek invasion of the Earth where the disgusting Kaled misfits had enslaved humanity - you'd think after having it done to them on a vast level humans would have thought twice, but no. Like the Daleks who had discovered that 'cheap, expendable humanoid labourers' were a better substitute to machines, the humans had learnt the same disturbing lesson and began using innocent aliens who had either been conquered by them and forced to work, or had simply been caught in the wrong place at the wrong time. It was bad enough that the Daleks saw all life as worthless beings if it wasn't their own twisted form of life, but what made it worse in the humans' case was the humans were better than all that.

All those times coupled with how often he'd stepped into a point in their history where humans were fighting each other needlessly in their petty feuds had made the Doctor think about how he'd come to like and to care so much for a race of people who even so close to the end of the universe hadn't really changed; the Toclafane's origins were still a mystery to the Time Lord, but he would really be surprised if the Master hadn't found them desperate enough to get them to serve him just so then he'd save them from the end of the universe when all other races had accepted their fate and died. The Doctor would not be surprised if the Master had manipulated them to make them physically and psychology suited to his purposes. In their spherical casings which housed a complete human head and a personality like a warped and psychotic child, the Toclafane had not cared they were slaughtering their ancestors who the Master enslaved through them, deeming it 'fun.' Hearing that childlike voice so many times over the course of the Year that Never Was, and realising what it really was, made the Doctor sick.

But the Ood didn't deserve to be enslaved by humans simply because the Ood had been an easy conquest, he had met them twice now but the first time he'd met them he had been more focused on finding the TARDIS after it had fallen down that chasm to where the Beast was chained by than ancient people, but he hadn't had any inkling of just how dark and painful that enslavement went. If he had then he would have done all he could've done for them, but when the Beast had taken control over their minds to a point where he doubted the Ood Brain itself could have withstood it he had simply left them to die without much thought. Now he felt guilty over it.

Finding out that the Ood Sphere was in the same star system as the Sense Sphere, the homeworld of the Sensorites had definitely brought back memories, and reminded him how unpleasant humans could really be, though his experiences on the Ood Sphere had been one of those unpleasant trips where he wondered, truly wondered, if the human race was even worth it. He had been frightened for the Sensorites after seeing the parade ground how that fallen Ood had been beaten so viciously; it had been a long time since his meeting with them, a very long time, but he had come to admire them during those days when the TARDIS had landed on Maitland's ship and immediately found himself dealing with the Sensorites who'd imprisoned the crew in a mental nightmare that reduced them into gibbering wrecks.

After finding out that a small group from INNER had poisoned their water supply, the Doctor could very well understand the fearful attitudes of the Sensorites. He wouldn't be surprised if the Ood and the Sensorites were aware of each other and were allies after a fashion or had a mutual ancestor since they shared so many physical as well as psychic traits, and he was worried the Sensorites had begun to feel justified by their fear of humans despite how Maitland's crew had come around to see things from their captor's point of view and how they themselves helped him find those three astronauts who'd been driven insane and driven to steal the minerals of the planet after wiping out the Sensorites when they saw and probably telepathically witnessed the savage way humans lobotomised the Ood for use as slaves.

The Doctor had seen many sick and disgusting things in his life, but when he'd realised that the translation sphere replaced the Ood hindbrain they carried in their hands, he had truly resisted the urge to cry and vomit at the same time. Humans! Why was it at times they were pure evil, cruel beyond reason, and savage beyond compare?

Sometimes the Doctor wondered why he shouldn't simply let them be wiped out - timelines aside - because there were times he felt that such an act of genocide was justifiable, and what happened with the Ood was justified in his mind. He hadn't bothered trying to convince the Ood to simply let the humans live, especially after what he and Donna had seen with those unprocessed Ood though truthfully at the time he'd been occupied with trying to get him and Donna released from those handcuffs, he was just grateful the Ood brain was reasonable enough to recognise himself and Donna as friends; Donna might have been human, but she had more kindness and compassion than anyone at Ood Operations. She had comforted the dying Ood they had met in the snow after their arrival, spoke to them during that conference thing, and later on cried when he telepathically allowed her to listen to their song of captivity. He hadn't thought any less of her for crying, he himself had been trying very hard to keep his own composure, though he felt anger more than anything else.

The Doctor smiled fondly as he thought of her. He had no intention of hurting her the way Lance had, and he definitely didn't plan on repeating the same mistakes he had made with Martha, but Donna was more than willing to stand up for herself than others. Besides, she had made her feelings very clear and wasn't afraid to slap him if she thought he was offending her, so that was a plus. He would always cherish the memory of seeing Halpen being taken aback by her attitude. His smile faded as he remembered how he had wondered if taking on other people with him on his travels was worth it after seeing what had happened to Astrid, to say nothing of Martha's departure. But still, Donna wasn't like those two, and he hoped he wouldn't repeat or make mistakes with her.

He also remembered how taken aback she was when Halpen was turned into an Ood, and the Doctor had to admit that as punishments went that the Ood certainly knew how to inflict punishments as nicely and as befitting as possible, and it apparently only took 5 years for Ood Sigma to do it, replace all the so called hair tonic with Ood genetic material.

For years Halpen had hated the Ood, derided them, cursed them, ordered their deaths whenever the so called 'red eye' disease showed itself, and he wasn't the only one to do so and now he was an Ood himself, forced to forever carry a hindbrain in his hands and listen to the Ood's telepathy for the rest of his life. The Doctor knew that deep inside Halpen hated what had happened to him, but the Ood's natural pacifism had probably spread to him, so he would probably become more and more Ood-like as time passed. Either way the Doctor didn't care, Halpen deserved it for what he and his family and others had done for centuries. If he did develop traits of his new species, there would still be enough human bigotry to wish he had died. Halpen was now a prisoner in his own body, and he actually felt he deserved it.

The Doctor was so locked in his mind that he didn't notice it when Donna walked in. "Doctor?" she asked.

He jumped. "Donna, you okay?" he asked with his usual grin.

She nodded, her earlier enthusiasm for arriving on a planet in her future having faded because of what she saw, and the Doctor couldn't blame her. "Yeah, I was just thinking about the Ood and what happened. Do you think they'll be okay?"

The Doctor turned his attention back to the console with a sigh. "I was thinking about them too," he confessed. "I think the Ood'll be okay; their song travelled to every human, so they know now what they've done, how they've abused an entire species for centuries. There will be humans who'll probably not care about what they've done, but I don't know for sure what will happen now to them. Give me time and I'll tell you."

"What do you mean? I'd thought you knew everything."

How could he explain this? The Doctor looked at Donna squarely from where he was. "Do you remember when we were in Pompeii and I told you about fixed and flux points in time?"

At her nod, he continued. "Well, because of those fixed and flux points, time is a lot more fluid than you think. When we arrived on the Ood Sphere, Halpen was probably planning on destroying the Ood Brain, and the massacre would've happened anyway since the Ood brain had had enough of the oppression, and if we weren't there, then the death toll would have been much worse, and he would've succeeded in destroying the Brain, maybe he even transformed into an Ood when the whole place exploded, but our intervention stopped that and prevented the extermination of the whole species. There are always possibilities for how the timelines can change, Donna. The problem is time is still changing for the Ood, so it's hard for me to get an idea of what will happen to them."

While the Doctor felt uncomfortable using the word extermination since it conjured some truly horrible memories of the Daleks, Donna blinked at him in confusion. "Hold on, are you saying we've changed history? I thought you didn't like doing that, you know being a Time Lord and all that."

"Time Lords don't as a rule, but there are some things you can tweak without causing a lot of damage. If the death of the Ood was going to happen, and was meant to happen, I wouldn't have stopped it - I'm sorry, but its true - but I could stop it when we were there. It was a point in flux, so we were free to interact with it; now the universe is without the rest of my people, I have to be even more careful about where and when I visit in case something goes really bad. Now…..," he took a moment to sigh as his senses told him time was shifting, "the universe is changing slightly because of our intervention, with the Ood's survival."

Donna blinked at him again. "I still don't get it."

The Doctor led her to the pilot's chair and they sat down. "Let me speak so I can get it all out, you can ask questions afterwards. When people think about time travel, they can't help but think about it like space or car travel; you get into the machine and travel to where you want to go, and that's it. Not true. Everywhere you travel to, there are risks and dangers as you travel through time and space. You have to be careful of historical events." The Doctor took a breath. "When I was travelling with Rose, we went back in time to when her father had died, and she changed history by saving his life. Because he had died when she was a child, it was a fixed event in her timeline and it had a hand of shaping her as a person. It caused a lot of damage, and creatures out of time came out to wipe out the human race."

"What?"

The Doctor nodded. "That's not all. There was another case where….someone ripped the TARDIS to pieces to change history, and it created an alternate timeline where the human race was enslaved to conquer the universe."

Donna jumped out of the seat. "What?!

"Sit down," the Doctor tugged her down. "It was sorted out. But the fact is, if it was left alone then the universe's history would have been changed forever. The Time Lords' presence kept the universe's timeline stable and linear, but you can tweak events to have different outcomes providing you are careful. Every time you walk out of those doors, Donna, you can change history ever so slightly. TARDISes were designed to never change history. Whenever they landed on worlds, the crews were supposed to stay inside to prevent historical changes and just observe what was happening around them, no matter how small, and they were fitted with devices that change the TARDIS's outer form."

"I thought they were supposed to look like blue boxes," Donna said, "you mean they can change their shape to appear like cars?"

"Yeah. My TARDIS can't do that, but she used to. The circuit controlling the changes was faulty and it was one of those systems that broke down. Time and history are changing because of our involvement on the Ood Sphere, but its a good change compared to altering your childhood like Rose's attempt. I don't know exactly what the change will bring, but you knows? Maybe the Ood will go onto becoming a race better than humans when it comes to exploring; they might be passive, but anything is possible. I just wish the humans had left that part of the cosmos alone."

Donna frowned, and the Doctor sighed. He hated to do this, but he needed to. "Do you remember when we were in Ood Operations listening to those lies about how well treated the Ood were, and we saw that map showing the Second Great and Bountiful Human empire?" At her nod he went on. "I told you I'd visited that part of the universe before, well I have. The Ood Sphere is close to the planet Sense Sphere, the homeworld of the Sensorites."

"Who are they?"

"Another race of telepaths, but more technically advanced than the Ood. They've always had an uneasy relationship with humans. When I first met the Sensorites they were holding the crew of a human ship prisoner because the last time they'd had humans on their world they had opened their minds to the Sensorites, exposing them to the greed of humans when they realised the planet was rich in precious metals the Empire needed. Anyway, those earlier humans tried to escape and their ship was destroyed, but the Sensorites didn't know 3 of the original crew had survived. They went mad, Donna," the Doctor went on, his mind casting itself back to the earlier days of his first travels with Ian and Barbara after the pair blundered into the TARDIS in Totter's Yard. "They had used the Sensorites' telepathic enhancers to drive themselves into the delusion they were at war with the Sensorites, and they had begun using deadly nightshade - I still don't know where they'd gotten it - and began pumping it into the aqueduct into the city of the Sensorites. All they wanted was the planet's mineral wealth."

"Oh my god," Donna whispered in horror.

"The Sensorites believed the humans had unleashed some kind of plague on them, they were right in a way but they were wrong in that it was a plague."

"What happened?"

The Doctor sighed. "The TARDIS landed on another human ship sometime in the 28th century, but it was practically dead. Me, Ian, Barbara and Susan - my companions at the time," he explained, hoping Donna didn't ask too much about any of them because he didn't want to talk about Susan; the memory of her departure to say nothing about what could have happened to her would haunt him always, "found the crew virtually dead. But they weren't. The Sensorites had terrified them into remaining in orbit of their planet. The crew had visited the planet and found the same minerals the original crew had, but this time the Sensorites had no intention of letting them go. They held them there by fear, and they stole the TARDIS lock. It took time to bargain with the First Elder of the Sensorites to let me try to cure the disease, and Ian himself was affected."

"But you did cure it, right?" Donna said though it was clear she knew the answer.

"Yeah. I cured it alright. I also revealed it was a simple case of poisoning instead of a disease. But there were a few Sensorites who felt humans were too dangerous, so they conspired against us - they sabotaged efforts to find and isolate the poison, even intercepting a consignment of the antidote when Ian himself was poisoned, and they nearly trapped Ian and I when we both went into the aqueduct tunnels to find the source of the poison - I'd gone in earlier to take a look, and found some of the nightshade that the original party had brought with them though why they'd keep a fatal plant poison is beyond me, but I was attacked - and they also tried kidnapping one of the second ship's crew, a girl called Carol. She was quickly found and the one behind it was exiled, but looking back I know he was only trying to save his race, and he may have had a point to fear and hate humans."

Donna had been remarkably silent during his story even though she knew he was giving her only the most basic details of what had happened on the Sense Sphere. "Do you think they're okay, the Sensorites I mean?"

"I don't know, " the Doctor answered honestly, thinking that he had let the Sensorites as down as badly as he had the Silurians. "I'd heard that they were forced to surrender to the Earth Empire in the 30th century, not two hundred years after my visit. Besides when humans find something useful in one solar system, they rarely leave the whole place alone. It's possible that through the humans the Sensorites have moved on from just being a race of simple telepaths into heaven alone knows what. But I would be very surprised if they hadn't been aware of the Ood, and what happened to them," the Doctor explained.

Donna shook her head. "The more I hear what my lot-I mean what humans do out here makes me want to throw up," she whispered. She shook her head. "I don't get it - you watch things like Star Trek and they say life will become amazing. But the reality's different isn't it?"

The Doctor was reminded of the time he and Rose had met the Ood and Rose had said something similar, but he didn't tell Donna that. But unlike that time this time he answered it as honestly as he could. "Life is different in films and on TV, Donna, than in real life. You know that. When you were younger, didn't you ever plan on getting a good job only to be faced by one temp position after another?" he said as gently as he could. "I'm not deriding you Donna, I think its brilliant you've been doing so many things," he said as quickly as he could without making it look like he was criticising her on how her life had gone,, and the look she sent back at him told him she wasn't convinced "but the point is many people driving research into space travel in your time are taken in by the dreams of visiting other planets using Star Trek warp drive. In fact there will be a light speed ship with a resemblance to the Enterprise," he grinned at the look on her face, "but the reality will be a wakeup call. Over the centuries humans will change from a warlike race determined to build empire after empire, and then they would found republics and federations. It's so hard to keep up."

The Doctor looked Donna straight in the eye. "At times there will be breakouts where the humans would send out colony ship after colony ship, or ships carrying embryos off into the void between galaxies scattering them through space like the seed pods of a flower, so the whole process of building, exploring, colonising and conquering will begin again and again. Some of those groups will be hostile, others truly exploitive and others will be like Captain Kirk who explore the universe peacefully. And the cycle where some will become greedy and want more will happen again and again. It happens Donna."

Donna couldn't help but see the logic, but she didn't have to like it. "I don't like the thought of my people becoming slavers, after everything that happened in history-"

"Slavery is one of the oldest concepts in the universe," the Doctor interrupted. "It's existed for centuries long before humans even became aware of the so called appeal to have others break their backs rowing a war galley or mining a quarry to save time and expense. Human slavery is banned in the future, but since many humans believe alien life doesn't matter they don't care."

Donna flinched at the news humans would be as xenophobic as they were in some books and movies in real life. "Don't we ever get invaded?" she asked, not checking her words. She had become so ashamed with her race in the past 10 minutes that she had spoken as if she didn't want to be human, but this time she was too agitated to check her words.

The Doctor knew what Donna was asking and nodded. "More times than I can count, and each time humans would be battered down and forced to work. I've seen it so many times, and for small groups of people the thought of enslaving others becomes disgusting but for others who haven't experienced it being done to them slavery is an easy way to get labour."

Donna looked down and sad. It was clear the pictures she'd painted in her head of seeing all of time and space were becoming sour, and the Doctor couldn't blame her. His one hope was she didn't decide to leave. "It's not always like this Donna," he whispered. "I can't guarantee we won't meet thoughtless people who don't realise what they're doing, but its not all bad."

Even as he said those words the Doctor knew he was having trouble believing them himself. He had lived a very long time and had seen many disappointing things about his favourite planet and its people. But hopefully he could prove to himself and Donna that there was still beauty out there.

Donna looked at him strangely for a second before she spoke again. "Doctor, what did Ood-Sigma mean when he said your song was ending?" she asked.

The Doctor blinked at the question. He hadn't really paid it much thought during his reverie, hoping instead to simply think about their recent adventure, the Sensorites, and human nature in general along with the hard to explain concepts of time travel. Now he couldn't help but think about Ood-Sigma's statement.

He was silent for a few moments while he pondered on the question, and then he decided to be honest with his friend. "I think he means…I'm going to die," he replied.

Donna gaped at him, but before she could speak he hurried on quickly. "Time Lords have this….trick, this means of returning from certain death, but it changes everything. For a start, one Time Lord could resemble a tall man with thick blond curls in one incarnation before regenerating and looking like a small man with brown hair. There's a huge physical and mental change, every cell is altered, and different aspects of personality come out," the Doctor said, adding, "I think Sigma was telling me that my current incarnation would end soon, and being a time traveller that could mean anytime now."

Donna looked overwhelmed by the new influx of information about him. "How many times have you done this?"

The Doctor gave her a humourless grin despite trying to reassure her. It was hard to find humour in such a painful topic since he didn't have that many regenerations left. "Quite a few times," he said, "I've been around for a long time, Donna. I've spent most of my life travelling the universe and seeing the wonders out there. But I have a habit of getting involved with things, and it usually ends up with my body being fatally damaged to the point I need to change."

He hoped Donna didn't ask about how many lives he'd had and how many he had left, it wasn't a comfortable topic with him, especially with the incarnation he would love very much to simply forget during the Time War. He might have done his best to avoid thinking of the him at that time in his life where so many lives had been lost, but it was still a regeneration.

Now he had no choice but to remember Ood-Signma's warning about the future, the Doctor now knew he would need to begin counting down the days he had left before his present life died. What a charming thing for him to do.

Author's notes.

The War Chief was a renegade Time Lord who allied with a race of warriors who wanted to take control of the galaxy, but needed an army to do it, so they turned to humans. With the War Chief's help the War Lords kidnapped humans from the Roman Empire through to the First World War, mentally conditioned them and forced them to fight. The Second Doctor managed to liberate the soldiers, but he couldn't send them home, so he summoned the Time Lords who would go on to exile him to Earth. The War Chief, afraid of the Time Lords, tried to escape, but was killed by the War Lords when they realised he was using them.

Reginald Styles was a politician and diplomat who was mistakenly believed by 22nd century soldiers who were fighting the Daleks that he had paved the way for a series of nuclear wars which left the planet wide open for the Dalek invasion. Instead it was one of their own number who exploded the bomb as part of a paradox.

Icthar and the Silurians tried a variety of ways to take over the Earth from humans via a plague, a war, and they tried to destroy the Van Allen belt to wipe out humanity. Eventually the Sixth Doctor in an audio drama discovered Silurian scientists had genetically altered our ancestors to taste good, but this made us more intelligent.

The Selachians, otherwise known as the Ockorans, were once a peaceful race who were content to live peacefully before aliens came to their planet had used it as a holiday spot - and they began hunting the Ockorans because they believed they weren't sentient until the Ockorans developed powerful battle suits and launched an attack during a festival. They went on to build an interstellar empire before a trade deal went wrong with Earth and a war erupted that eventually saw the extinction of the Selachians.

Anyway what did you think about my explanations about how time travel works - its so hard to put into words even if you can imagine how it works.