The Doctor had literally just been shot by the Daleks. Well, one Dalek. Same difference, and the Dalek responsible for the shooting was gone anyway, although the Daleks on the whole weren't, a fact which, to say the least, worried the combined population of the planet.
The Doctor's friends had dragged him into the TARDIS to, as Jack and Rose knew, although Donna was completely in the dark, regenerate. Rose knelt by the Doctor as they laid him down; although she knew perfectly well what was about to happen, accepting it was… less of a simple matter.
"What do we do? There must be some medicine or something!" Donna yelled, not understanding.
"Just step back. Rose!" Jack snapped at Rose, pulling her away. "Do as I say and stand back!"
His voice became more tender, softer, and he tried to comfort her. "He's dying and you know what happens next!"
"What do you mean?" Donna yelled – yelling at the world because no one was listening, of course. The Doctor winced in pain – clearly, he was trying to keep it under control.
"But he can't!" Rose yelled. "Not now! I came all this way!"
The Doctor heard that and two things came into his head, two very different and opposing thoughts.
Thought numero uno. 'I have to stop myself. There has to be some way I can prevent myself regenerating.'
'Why?' the second thought asked.
'Because Rose doesn't want me to.'
'So? Rose knows what regenerating is. Donna's gonna be the one to convince.'
'But Rose is so upset, can't you see…?'
These two thoughts waged war with one another, each trying to get the point across. Finally, a decision had to be reached, and he raised his hand, gazing at it, confirming the worst.
It glowed gold.
'The hand. Siphon the regenerative energy off into the hand.'
'Too risky. Too many variables. Too much in the way of chance and happenstance, and that's not counting the possibility of metacrisis. Regeneration is tried and trusted.'
'I don't want to go.'
'Today, we don't have a real choice. I'm sorry.'
"It's starting!" the Doctor warned his friends.
"Here we go!" Jack yelled. He pulled Rose away and gathered them to him, watching as the Doctor brought himself to standing. "Good luck, Doctor!"
"Will someone please tell me what is going on?" Donna yelled.
Rose tried to calm herself. "When he's dying, his body, it repairs itself, it changes..." The façade broke. She couldn't allow it. She loved this Doctor, and she couldn't deal with him leaving her. Not again. Not after the last time. He had been so different. "But you can't!" she yelled, as if the very act of yelling would overcome the natural course of the biology of a Time Lord.
"I'm sorry, it's too late," the Doctor told her. And then, the last words.
"I don't want to, but… I have to go."
And then, the fire. A golden glow that burned across the human onlookers vision, forcing them to look away. A man let his old life burn away, and a new one take it's place.
She didn't want to open her eyes. When she opened them, he would be gone, and she would have lost him forever… and after she had come so far...
"Right then," the new voice came.
She definitely didn't want to open her eyes. No sir. She really didn't want to open her…
"Legs! Still got legs!"
She opened her eyes.
A young man in the Doctor's suit was examining his arms and legs and fingers, commenting on them. His hair was long, his face less careworn, his eyes blue and bright.
"Ok, nose – I've… had worse, chin – blimey… hair, hair… I'm a girl? No! No, wait – I'm not a girl…"
He was speaking very quickly. And then he stopped, and looked at his companions. And smiled.
"Donna Noble!" he ran right up to her and hugged her. "Oh, you, you brilliant Donna you! You're brilliant! Amazing! Magnificent! Molto Bene! Oh hang on…"
He came away and frowned.
"No, not liking the Italian. Maybe, Sehr Gut? Is German really my thing? Maybe just 'really good' - I mean, Earth is Earth, what's one language to another, eh? English is Germanic in Orion. Admittedly, lot of French in theremtoo..." he babbled, looking at his companions for feedback which was studiously not forthcoming, and then he was frowning at them.
"What's wrong with you all?" he asked very seriously. Before they could reply, the lights went out. The Doctor looked up.
"I've forgotten something," he declared. "Something important."
"Daleks?" Jack suggested. The Doctor laughed and jumped and clapped and pointed at Jack's face.
"Yes! Yes, the Daleks! I remember! Oh wait…"
His face fell, and assumed a serious face, and then he looked at the console. He walked over, and flicked the defunct switches. He flicked them again. Then he looked at his companions. Specifically, at Rose.
"Right," he said. "I guess we're about to arrive at Dalek HQ. And I'm not exactly in a fit state to fight them, what with the fact that I'm kinda still going – I could fall over any minute, or start belching gold, glittery regeneration… stuff. So, here's the plan…"
He grabbed Jack and Donna by the shoulder – ignoring Rose completely.
"Jack, you stay in here, I don't trust the Daleks as far as I could throw 'em. If they try to destroy the TARDIS – and they might – then press that blue button there…" he pointed at a control, "and the TARDIS will use the HADS – works on a separate system, so it should be fine."
Jack nodded. Professional, as always. The new Doctor smiled, and turned to Donna.
"Right – yes, it's still me, and if you want proof, wedding dress, Wilf, Martian boy, Robot Santa's, and the rest," he said, rattling the list off on his fingers.
Donna looked right at him, and then laughed.
"You look terrible," she said at last, and laughed. The Doctor laughed too.
"So all you have to do is follow me out, and stand still," he finished. "Sorry I can't think of a better idea, but you're clever, you'll figure something out, I just know it."
And then, he turned his new, blue gaze on Rose. Rose, who looked at him with such reluctance.
"Only one question," he said, slowly. "Do you still trust me?"
She looked right at him. The answer didn't come. He looked right at her. No answer. He waited.
"Well?" he asked.