Rose swung her legs as she sat to the side of the TARDIS console watching as the Doctor ran this way and that, occasionally using his feet to try and press a button whilst his arm was stretched around the other side, attempting to pull down a lever. She vaguely wondered, not for the first time, why the Timelords had made the thing so difficult to fly. The thought was fleeting, as she was listening to the Doctor talk at a hundred miles per hour. Rose knew that she was never going to understand most of what he was saying and had given up asking him to explain a long time ago, but she also learnt that if you weren't at least trying to pay attention then chances were you'd miss something important.

It had been a good couple of months now, but still Rose couldn't help comparing this new, fast-talking man, bouncing around like an excitable puppy, to the one she'd first met in that shop in London. They were so different it was unbelievable, yet every so often there was a flash of the old Doctor; a grin, a glance, an old joke. It wasn't as though Rose didn't believe him; it was just taking some time for her to get her head around it. It must be second nature to him by now, she wondered how many different faces he'd had, in all his nine hundred years.

Rose hadn't realised that her mind had wandered off from the Doctor's ramblings. That was until his voice suddenly took a more serious tone.

"No. No no no no no!" He said in quick succession. Rose always thought he sounded like he was telling the TARDIS off when he did that, like a dog who'd eaten his slippers.

At this point he disappeared around the other side of the console, still muttering about things not being good, and that something or other was interfering with a whatchamacallit and that that could result in a hoojamaflip... Then suddenly he went quiet.

"Doctor?" Rose ventured hesitantly. Quiet was never good. Then suddenly he started talking again, but not in a tone she liked.

"What?" He started to stammer, "W-what?" He stepped back into view, his eyes wide staring at something still out of Rose's eye line. His mouth was moving without any sound coming from it before he managed to choke out one last "What?!"

"Who are you?!" An incredulous voice came from behind the console, one that Rose found strangely familiar. "What are you doing here?" The thick northern accent became suddenly hostile.

"That's, that's not possible." Stammered the Doctor.

"Doctor? Doctor what is it?" Rose finally managed to pluck up the courage to ask.

"Rose?" Came the northern accent again. Rose started. How did he know her name? "Rose is that you?" Suddenly a face came peering around the console, a face that Rose thought she'd never see again.

It was the Doctor. The old Doctor. Complete with leather jacket and closely cropped hair. Rose nearly fainted on the spot.

"I thought you were having dinner with your mum?" He looked slightly confused. Then he suddenly remembered the new Doctor, who was still standing to one side, like he couldn't quite believe what he was seeing. "And who are you? How did you get on here?" He rounded on him, interrogating.

Rose didn't know what to do. Did this mean that the new Doctor wasn't the Doctor at all? Was he some sort of imposter? No, that couldn't be right; she'd seen the regeneration, right there in front of her eyes.

"Um, well, I'm, um…" The new Doctor stammered slightly, obviously torn between telling the truth and the implications of that truth.

"You had better tell me who you are before I chuck you out of here, and we are flying in Earth's orbit right now, so that might be quite a hot fall." Threatened old Doctor.

"Doctor." Rose decided now was the time to try and help, she knew both of these Doctors and she wasn't sure how well it would turn out without her help. They both turned towards her, but Rose focused on the new Doctor. "Doctor, what's happened? I think you need to explain, to everyone." At this Rose looked pointedly to the old Doctor.

"Right, yes." New Doctor seemed to be trying to shake himself out of his state of shock. The old Doctor was now looking very confused.

"Rose? You know this guy?" He asked, suddenly looking uncertain as to what was happening. "Why are you calling him Doctor? What's going on?"

"Well the thing is," Rose hesitated, not quite sure how to say this. She decided to go slowly, considering she wasn't all that certain what was happening herself, "That is the Doctor."

"No," The Doctor replied, almost laughing out of confusion, "I'm the Doctor."

"Yeah, but he's the Doctor too." Rose replied, doing her best to explain, but feeling she wasn't doing a good job of it. Meanwhile the new Doctor was fiddling about with the TARDIS screen, that look of confused determination on his face that she loved so much.

"What are you talking about? Rose? That man is not the Doctor. I am." He still had that concerned laughter in his voice, like he couldn't quite believe he had to say this.

"Doctor, listen to me." Rose said firmly but gently at the same time. How did she end up in these situations? "I'm not entirely sure how, I think that's what he's trying to figure out now," She gestured with her head to the new Doctor, who had cables out and was doing something to them with the sonic screwdriver. When he saw this, the old Doctor pointed and went to say something before Rose put her hands up to stop him. "But," She continued forcefully, "That's the Doctor, the new Doctor, he's you." She paused to take a deep breath. She knew what she had to say but she wasn't sure how the old Doctor would take it. "You regenerated." She said as she exhaled.

The Doctor stared at her, dumbfounded. Rose glanced behind her and the new Doctor had paused, looking up over the glasses he put on whenever he was fiddling with TARDIS parts. The old Doctor stood there for a good minute, not quite knowing what to say. Eventually he seemed to snap out of it.

"So how are you here?" He finally said, staring at the new Doctor in much the same way the new Doctor had stared at him when he'd first arrived.

"Ah!" The new Doctor jumped up, snatching his glasses off his face and looking curiously at the old Doctor, who stiffened as the new Doctor showed off his impressive talent for invading personal space, "The question is, how are you here? I haven't gone anywhere, you're in my time. It probably would make much more sense if I were in your time, because that's just me going back to a time when you were…" He paused then, looking for the right word, "around."

The old Doctor grinned. "You don't have to be all gentle with my feelings," he offered, looking slightly amused, "I knew I wasn't going to be around forever."

The new Doctor looked at him for a moment, and Rose thought she saw a sadness in his eyes. Then he grinned and she wondered whether she hadn't imagined it.

"Well, in any case, that would have been more plausible. I even could have dealt with a sort of TARDIS collision, maybe a shield malfunction, like a, like a time crash maybe?" The new Doctor was in full swing now and Rose felt herself being swept along with him, that thrill of an adventure starting to pulse through her veins. "But this? This isn't, shouldn't be possible!" The new Doctor continued to rant to himself, whilst the old Doctor came up behind Rose.

"Rose," he said, for once showing how sad he was, "were you there?" She didn't have to ask him what he meant.

"Yes." She said quietly. "You saved my life." He smiled a bit at that.

"What's he like?" He nodded toward the new Doctor, obviously unsure about how he felt about it.

"He's… Different." Rose struggled to find the right words. "He's not you, but you're in there. Sometimes I can see you in him." She didn't feel like she was doing a good enough job at explaining, and she suddenly felt guilty, like she was cheating on the old Doctor with his newer version.

"Rose." he whispered looking down, it sounded like a sad plea. Then he looked up at her, staring straight into her eyes. "Does he love you like I do?"

Rose didn't know what to say, but before she had the chance a voice came from behind the old Doctor.

"Of course I do." It was the new Doctor and he had an uncharacteristically serious expression. The old Doctor turned to face him and they stood there staring at each other.

"How? How can you love her like I do? No one can." The old Doctor seemed to despair as he said this.

"I can. Because I'm you." The new Doctor maintained eye contact with the old, and they seemed as though they were having a silent conversation with each other. Finally the new Doctor spoke again.

"I can get you home." He said simply. The old Doctor nodded.

"Can I have a moment?" He asked.

"Of course." The new Doctor turned away and walked to the other side of the console and started fiddling again. Rose has the odd sensation that he was avoiding looking at her. The old Doctor turned to face her.

"I guess this is goodbye then." His voice faltering at the end of his sentence.

"Don't be silly!" Rose grinned at him. "You'll see me when you get back, a younger version of me perhaps but," Rose hugged him tightly and then looked him in the eye, her hands resting on his shoulders, "I'm there with you right till the end."

"Was I…" The Doctor faltered, not sure if he wanted to know the answer to his question, "Did I do a good job?" He closed his eyes, shielding himself from her response. Rose put a finger under his chin and made him look at her.

"You were fantastic."