Jack said nothing, but was shocked when he saw the Doctor snap the man's neck in one single fluid movement of only one arm. Losing Rose had done something to him, had made him more dangerous than he'd ever seen anyone before, let alone a Time Lord.
As he strode out in front of him and Lynda, he felt a dark shadow cross his mind.
The Doctor hadn't just cared for Rose as a friend; it was much deeper than that. It was love.
He'd seen throughout their adventures, and he had silently hoped that his eyes were deceiving him, but it was now fully obvious to him that it was real.
There was a brutality and coldness to how he moved now, and it went all the way to the expression in his eyes. Emotionless and as solidly closed as iron walls, it was a look that anyone could read: deadly. He was ruthless, expressionless.
And it terrified Jack.
He'd seen his share of brutality, but never anything like this.
There was something about it that was primal, and utterly merciless. He wanted nothing more than to not be near the Doctor in that moment for fear of the man turning on him and not recognizing who he was and turning his anger on him.
The moment that he'd seen the Doctor react to her death, he knew that something had started to bend inside of him…
…and now it had snapped.
The only that had ever been holding him back from snapping had been Rose.
And now she was gone.
And Jack wasn't sure that he could even bring the Doctor back from it. He was a Time Lord gone mad, and that was not a good thing. All of that power unleashed in pure fury and in a state of revenge, hell bent on destroying everything in his path.
And that was when Jack knew that he had to see if it was possible that Rose could still be alive, because if she really had been killed…
Well, there would soon be no more Time Lords.
He had to try.
A.N. - This was something that came to my mind after seeing the episode where Rose was supposedly killed. When I watched Ninth's reaction to Rose's "death", I was floored by the strength of Chris Eccleston's performance of the anger and anguish. So I wrote this. Tell me what you think!