A/N: The beginning bit are actual lines from the episode, the better to show canon diverting to AU. The rest is wishful thinking.
November 21, 2059
The Doctor reveled in his own audacity, "For a long time now, I thought I was just a survivor, but I'm not. I'm the winner. That's who I am. The Time Lord Victorious."
"And there's no one to stop you," Adelaide said with an edge to her voice.
"No," he answered curtly. It almost sounded like a dare to contradict him, him who had spat in the face of time itself.
She countered him forcefully, "This is wrong, Doctor. I don't care who you are. The Time Lord Victorious is wrong."
He paused for a brief moment, as if at a crossroads. He didn't know what it was about her. It could have been how scared she looked of him, it could have been the way she told him off, or it could have been her eyes. Her piercing blue eyes that didn't have rings of gold circling the irises, but still seemed to see right through him. It was her eyes he decided. It was her blue eyes and the mocking snow that lightly fell around them on this dark night that made him offer her a proposition.
"You can come with me," he blurted out. It wasn't the quiet, hopeful desperation of a few Christmases ago. It was a forceful, pleading desperation that begged for help, for absolution.
"What?" Adelaide frowned at him confusedly, completely thrown by the suggestion and the sudden change in tone.
"Come with me," he repeated. "I can show you so much more than Mars. I can show you all the stars your granddaughter will explore." His voice began to speed up with excitement, his imagination taken by the idea and the possibilities, "I can show you your legacy. I can show you why they had to die, why you were supposed to die. I can give you so much more than you could ever think of. I can show you the Byzantine Empire, the Great Anarchy, the Beatles Revolution, and World War IV all in a day before popping over to the Pleiades for a spot of tea."
"You're insane," she told him in utter disbelief.
"You asked if I was alone, if I had no one to stop me. You could do it. You could stop me. You could make sure I leave the timelines intact."
"Are you asking me to be your keeper?" she asked incredulously.
"I'm asking you to be my companion. I show you all of space and you keep time safe from me. It's a fair enough bargain."
Adelaide could only stare at him, unsure what to say.
"You get me to pull the lever on Pompeii and I can show you the swaying mountains of Felspoon," he added flippantly.
"I couldn't do that. Pull the lever on - wait, was there an actual lever?"
He shook his head at her misunderstanding, "She's already done that, I meant hypothetically."
"She-?"
"So you want to come with me, then?" he cut her off sharply. "Come and see the stars. I'll show you what's really out there," he waggled his brows in that playful way.
Adelaide waited a beat before asking, "And what if I say no?"
The Doctor leaned back against the TARDIS, contemplating what could happen, "Well, I'll go on without you. I'll leave you here happy with your family so you can inspire your granddaughter by actually meeting and knowing her. I'll travel by myself." His voice took on a darker edge, "And I'll save the whole town. Not just someone. Everyone."
It was strange how sinister it sounded. But after what she had seen today, she knew how terrible it could be. There could be hope in death, and, ironically, he could uproot that with life. He couldn't go on like this. Not alone. He was a liability. And could she really go back to her family?
Adelaide glanced back at the familiar door, wondering if her daughter was working late into the night, or if Emily had dozed off in the rocking chair while trying to get little Susie to sleep. And what about little Susie? If Adelaide stepped through that door, would she ever make it to the stars? The Doctor had said it was her death that was the fixed point, that inspired Susie to take humanity out to the stars. How could she be sure that her survival would not jeopardize Susie's future? But what alternative was there? Her hand hovered briefly above her holster at the thought.
Adelaide turned to the Doctor, "Yes."
"Yes?"
"Yes, I'll go with you. You're bloody pathetic on your own."
"All right, then," he responded with a wide grin.
"And we aren't ever coming back here," the captain spat out. "I'm dead to them."
His smile faltered momentarily, "If that's what you want."
"It isn't what I want," she snapped, blue eyes flashing fiercely at him. "But needs must."
The Doctor nodded meekly and stepped into the TARDIS, leaving the door open for Adelaide to follow. He thought it best to give her a moment.
Adelaide looked back toward the dark red door of her daughter's home, trying to gain some strength from it before entering this battered blue door of the Doctor's spaceship. She reminded herself she was doing this for Susie. She was doing this for humanity.
Closing the door softly behind her, Adelaide walked toward the console. Her face formed a worried frown as she spotted the Doctor hunched over the controls, his grip on a lever so tight his knuckles were almost white. A moment later he was no longer so tensed up and his hands began moving the controls to ready the ship for dematerialization.
Feeling her gaze on him, the Doctor answered her unasked question, "I can feel the timelines changing to accommodate your survival. They don't like it much." His smirk told her that he didn't care for the effects on the timelines. His next words confirmed it. "How about Pompeii? How do you feel about a city where 20,000 people die? We should fix that. Pompeii doesn't burn and everyone lives!" His manic grin terrifies her.
"No!" Her sharp retort is so harsh that the Doctor actually flinches as though from a slap. "No," she repeats quietly. "We're leaving Earth, and we are never coming back to this planet again. You promised me the stars so show me the stars."
The Doctor studied her for a moment then nodded his acquiescence. He took a slow turn around the console, pulling levers and turning knobs, recalculating a destination.
"Where are we going?"
He looked up at her before quickly turning away again, "Felspoon. Apparently it's got mountains that sway in the breeze. Mountains that move. Can you imagine?" His voice had gone distant for the last sentence, the rhetorical question.
It concerned her, but Adelaide decided to leave it for another day. She had her own emotional whiplash to sort through right now, and she could not yet shoulder his as well. She settled on the jump seat, the events of the day and the burden of living suddenly weighing on her, as the entire room began to reverberate with a sound like keys in a blender.
Unbeknownst to the two weary travelers, in the snow outside Emily's house, a strange being with tentacles for a mouth appeared. It looked to where the TARDIS had stood only a moment ago, cocking its egg-shaped head to the side.
"Curious," it intoned, as the orb it held in its hand flashed in time with its voice. Or rather, its voice flashed in time with the orb. A moment passed, and it disappeared into the ether from whence it came.