I don't own Doctor Who.
What awaits us.
The Doctor took a deep breath as he studied the TARDIS shortly after Miss Wright walked back inside the console room after saying a final farewell to their Thal friends - the fluid link had been reinstalled and now he had refilled them with fresh mercury from the Dalek city, the power systems were fully restored, and now the old TARDIS was just waiting for the female schoolteacher to make her return.
But as he studied the console, keeping his expression as detached and as unemotional as possible while Susan and Chesterfield were nearby, the Doctor was left reeling after the encounter with the Daleks.
When he had seen that metal city composed of magnificent and undamaged buildings in a ruined and radioactive - although they hadn't known about the war by that point - he had known at once he had wanted to explore it, even alone, even without Susan there. After all, that was why he had left Gallifrey, wasn't it? To explore the universe of space and time. But there was more to the Doctor leaving Gallifrey than what people really thought; even Susan didn't know the full extent of his reasons.
Yes, yes, his involvement with the revolution and his political ties had drawn so much attention that the theft of an old Type 40 TARDIS was trivial. With how turbulent Time Lord politics was since it wasn't surprising so many student groups had the habit of springing up and trying to change the High Council and move it beyond the stagnation which had clouded Gallifrey like a shroud of boredom for aeons. Unfortunately, it never worked out, and as a result, nothing on Gallifrey changed and the student groups were forgotten and they were nothing more than memories in the member's minds as nothing more than adolescent mischief.
Not any more.
The Doctor hadn't really paid any attention to the myriad stories and rumours of lies, blackmail, alliances being made and broken… he now had trouble picturing all of the people involved in those days. Right now he doubted nothing barring Rassilon or Omega might be enough to change Time Lord society around.
He hadn't been involved.
He had been determined to escape Gallifrey.
A lot of it started when he was eight years old, and when he had been admitted into the Academy. At the time he had not wanted to become a Time Lord, and the whole life was placed on his defiant shoulders.
But when he had looked into the Untempered Schism…
The Doctor closed his eyes, remembering seeing for himself the Time Lords themselves being drawn into a Time War even more terrifying and deadly than the Time Wars of the past. He had not seen the full extent of the war, but he had seen enough to know it was so devastating even the Time Lords, the oldest, most powerful race in the universe, the one race who held the keys to time travel.
But what was more confusing was while there was one Time War, there were numerous alternate possibilities for it, with one outcome for all.
The end of Gallifrey.
Hence the reason why he had run away from the Schism.
When he had left Gallifrey, taking with him and Susan the Hand of Omega, the Doctor had planned on travelling and seeing the universe; with a whole universe full of galaxies just waiting for him to explore, millions upon trillions of planets, aeons of time, countless civilisations to meet, dozens of societies to visit, secrets of the universe to discover for himself without having to delve into the files of the Time Lords within the Matrix on Gallifrey - he did not want secondhand knowledge.
He had always wanted to seek knowledge for himself.
But at the same time, the Doctor had an ulterior motive; he would travel the universe trying to seek out who this great enemy who would engage his people in a war to the death while planning on keeping the Hand buried somewhere primitive and unnoticed so then he would be able to use it as a superweapon later if he needed to. It was rather extreme, but the Hand of Omega had come with him and Susan, not the other way around and there was nothing he could do; he couldn't take the stellar manipulator back to Gallifrey.
Just like there was a slim chance his plan to get Chesterton and Miss Wright back to Earth in 1963. The Doctor merely hoped the plan to use the Fast Return Switch worked; in theory, it should work. The TARDIS had not visited many destinations since they'd hurriedly left 1963, but as with many systems in the TARDIS, the Doctor was uncertain if that was another system that was malfunctioning. For all he knew, the Fast Return could send them back to a different time prior to 1963.
But he had to try.
While he had begun to slowly enjoy the company of the humans - it was rare Susan argued with him, and the Doctor actually enjoyed the humans who were so primitive their knowledge of time was so laughably naive and pathetic that he couldn't help but see them as lesser beings, but they argued with him and weren't afraid to push him. But they could not stay with him. They weren't adapted to live out among the stars, among the aeons of time. No, no, no, they would have to return to their own time.
Once the human schoolteacher was back inside, the Doctor nodded at his companions and granddaughter, and he closed the doors and prepared the Ship for flight.
But as he pulled the main dematerialisation control, and the Ship left Skaro and the Thals behind, the Doctor leaned over the Fast-Return Switch and tapped it. As the TARDIS accepted the command, the Doctor could not help but wonder what awaited him and Susan in the universe. But even a Time Lord could never hope to know what lay in his future, and considering the fact the Time War was drawing closer and closer, a Time War known to the Time Lords of old through temporal projections masked in the typical superstition - why the Time Lords had to mask everything in cloak and dagger, the Doctor did not know, he had no idea what awaited them.
Author's Note - I read somewhere the theory the First Doctor knew of the Time War coming up so he had come up with a plan for the Hand of Omega, which wandered into the TARDIS with him and Susan. But at the same time, the Doctor does not know the Daleks whom he's just left behind are the enemy of the Time War. Among the alternates was Faction Paradox who fought the Time Lords and the Eighth Doctor, which culminated in Gallifrey's destruction in The Ancestor Cell.