"Eleventh century?"

"Yeah."

"15,000BC?"

"Yup."

"Erm..." Rose struggled to think. "The creation of the Earth?"

"Of course! Several times. Amazing. I'll take you sometime." The Doctor grinned when Rose paused, still trying to catch him out. "You won't get me!"

Rose groaned. "I will, I will! There has to be somewhere you haven't travelled to, in the Earth's huge timeline..." She suddenly gasped, eyes wide. "Got it! 1978 - nothing massively memorable about it."

There was a pause. "Well?" Rose asked, when the Doctor didn't say anything.

The Doctor opened his mouth, then closed it again, frowning. "I think you may have got me... no, hang on. Hang on, hang on." He ran his hands through his hair.

"Hanging."

"I'm sure I've... yeah, definitely. No. Yeah. Oh, my head... All my memories are going through my head at once, trying to find the right year. It's like a very confusing and messed up slideshow."

Rose watched him from the other side of the console of the TARDIS with amusement. "Won't your head, like, explode or something? Ugh, that wouldn't be pretty."

Suddenly the Doctor stopped, and shook his head from side to side like a dog. Rose stared at him. "Did you accidentally put something in your coffee this morning?"

"There we go! Success. For your information, Miss Tyler, I did go to the year 1978, ages and ages ago. I only managed to pick the memory out because of the vivid hairstyles..."

Rose visibly sagged, and flopped down onto the console chair. "I guess you got me."

"Good and proper." The Doctor agreed, sitting down beside her. "Doctor 1 – Rose 0."

They were silent for a few moments, only the faint hum of the TARDIS lingering in the air. Suddenly Rose said, "What about planets? Don't tell me you've been to all of those?"

The Doctor laughed incredulously. "As if! There's millions of them – don't forget I'm only nine hundred and odd. I've still got so much exploring to do – that's why I never stop travelling."

"So why take me along with you? Why not find someone who knows more about the universe?" Rose asked, quietly. There was a light in her eyes, indicating that she wasn't being completely serious.

The Doctor didn't hesitate before replying, "Why take you? Who else would I talk to? Boast and brag about all my knowledge to?" He became more serious. "The fact that you don't know much makes it even more amazing when I show you it all. You've seen so little. Even I've not seen a lot. It's such a vast universe, you could travel and travel for centuries and just scratch the surface. Where's the fun if you don't share it with someone?" He paused. "Plus, everyone needs a hand to hold."

Rose looked at him, and for a second his reserve fell slightly away and through his eyes she caught a glimpse of the extreme heartache he had had to swallow down for so many years. She felt a tug in her chest – what she would give to take some of that pain away from him... The Doctor glanced at her, and smiled to let her know that he was alright. Rose felt for his hand. Finding it, she linked her fingers through his and squeezed his warm hand tightly.

A few minutes passed, the Doctor and Rose both lost in their own thoughts. Suddenly the Doctor seemed to come to, cleared his throat loudly and leapt up from the chair in his usual buoyant fashion. Rose smiled up at him.

"What's next on the agenda, then?" she asked enthusiastically.

"Up to you," came the reply.

Rose grinned. "My turn to choose, is it? Great." She thought for a moment. "How about we go to somewhere that's unfamiliar to both of us, for a change? I'm sick of you knowing everything - let's discover somewhere together." She glanced at the Doctor to see whether he approved of this idea.

The Doctor, who had been fiddling with the console, turned to face her. He was frowning slightly. "If it's somewhere I don't know, then I don't know what threats we are facing, do I? Being the know-it-all has it's advantages, you know," he added, giving her a rather cheesy grin.

"Yeah, but we can't run into trouble everywhere we go, can we? We might just have a nice quiet time..."

The Doctor raised a sceptical eyebrow. "God, I hate it when people say that. You just know something will happen. Have you not met us? We attract trouble like two super strength magnets."

Rose grimaced. "I know! We can't even go for an ice cream without the world nearly coming to an end." She suddenly laughed. "Oh well, don't bother about what you can't change. That's what my mum always says, anyway."

"And for once, she's right. Ready, then?"

Rose was taken aback at the sudden change of heart. God, she thought, he's confusing at times. "Ready!" she replied, taking hold of anything attached firmly to the console. The ride was rarely smooth, and she didn't fancy being flung about. "So where are we going?"

"No idea!" the Doctor admitted, as the TARDIS started shuddering and the rotor in the centre began moving up and down. "I'm letting the TARDIS decide..."